The Gunperson's Authoritative Internet Information Resource.
The Gun Zone banner

5.56mm graphicPart Three...

The 5.56 X 45mm: 1967-1973

A Chronology of Development by Daniel Watters

1967...

The USAF acquires 75 AR-18 for testing.

Howa Machinery Company of Nagoya, Japan buys the production rights to the AR-18 from ArmaLite.

Manufacture d'Armes de St-Etienne (MAS) of France begins development of a 5.56mm rifle. The project is led by Paul Tellie.

At Ruger, L. James Sullivan begins work on a scaled down M14 in 5.56mm. Several years (and modifications) later, it is released commercially as the Mini-14.

NATO initiates a general feasibility study into caseless ammunition.

Frankford Arsenal initiates the M16 Sight Enhancement Program to develop improved low-light sights, both iron and optical. Frankford's Pitman-Dunn Laboratory also begins research into caseless cartridges.

Frankford Arsenal and Lake City begin the development of gilding metal clad steel (GMCS) jackets for the construction of M196 Tracer projectiles. This was the result of reported jacket failures with the M196.

After acquiring 50,000 XM16E1-type rifles, the Philippine government purchases a production license from Colt for an XM16E1-type rifle and a 14.5" barreled carbine. Manufactured by Elisco Tool Company of Manila, Colt designates these variants, the Model 613-P and 653-P, respectively.

The Naval Ordnance Laboratory produces a subsonic 5.56mm cartridge for use by SEAL teams. The projectile is a truncated lead slug. Another effort uses Sierra hollowpoints. Both are reportedly used for shooting sentry animals, but neither provides the desired terminal performance.

Nosler constructs 500 solid steel projectiles plated with bronze. The 41 grain projectiles are intended for testing by Frankford Arsenal.

January: Colonel Yount notes an "urgent" requirement for swabs, bore brushes, chamber brushes, and cleaning rods.

The closed-end "birdcage" flash hider is included in new production M16/XM16E1 rifles.

The CAR-15 Commando is type classified as the "Submachine Gun, 5.56mm XM177" (USAF - no bolt closure device) and "Submachine Gun, 5.56mm XM177E1" (Army - w/ bolt closure device).

Colt files the report "Delrin Charging Handle Latch Report." The Delrin charging handle was designed in hopes of reducing user complaints concerning the charging handle unlatching while the weapon is firings. The 'Commando' models were considered to be the worse offenders in this regard. However, it is eventually found that the Delrin handle is simply not durable enough for field use.

The PMR Office publishes "A Review of Primer Sensitivity Requirements for 5.56mm Ammunition."

Colt's Foster Sturtevant receives US Patent #3,301,133 titled "Mechanism for Changing Rate of Automatic Fire."

The US Navy orders eight belt-fed Stoner 63A LMG for field testing by the SEALs in Vietnam.

FN builds five additional CAL prototypes.

NWM and its parent company Mauser - Industrie Werke Karlsruhe AG (IWK) of Germany introduce a quartet of 5.56x45mm loads to support the Stoner 63. This includes a 63 grain tungsten core AP load, a 700m-range tracer, and a training blank. Most interesting is the 77 grain FMJ load (2,722fps), which requires a 1-in-7.8" twist barrel.

ACTIV publishes "Evaluation Plan-XM148 Grenade Launcher." The primary purpose of this evaluation is to determine if the XM148 grenade launcher will operate effectively in the hands of the average soldier under combat conditions. A secondary purpose is to determine durability, maintainability, and future combat service support requirements. The evaluation of the XM148 grenade launcher is being conducted at the request of the Office of the Assistant Chief of Staff for Force Development and the CDC.

February: The XM16E1 rifle is classified as Standard 'A'. Its designation officially changes to "US Rifle, 5.56mm, M16A1."

General Johnson sends a memo titled "NATO Impact of SAWS Decision" to Secretary of the US Army Stanley Resor. While the standardization of the M16A1 is a concern to fellow NATO allies, Johnson suggests that US troops assigned to NATO will not replace their M14 rifles prior to Fiscal Year 1972. This would place the changeover safely behind the January 1968 expiration of the NATO standardization agreement.

Winchester/Western proposes altering the direct gas system of the M16 to a short-stroke gas system.

After only ~3,000 rifles are delivered, Singapore purchases a production license from Colt for the domestic manufacture of 150,000 M16 rifles. Chartered Industries of Singapore (CIS) will produce the M16S (no bolt-assist) rifles. Colt designates this variant the Model 614-S.

The SPIW executive committee reconvenes. To support a future reactivation of the program, AAI is awarded a "nominal fee" contract to continue improvements of their SPIW candidate. Two of the second-generation SPIW prototypes are returned to AAI for further modification and experimentation.

February-March: The Stoner 63A system begins field-testing in South Vietnam with Lima Company, Third Battalion, First Marine Regiment, First Marine Division. Most Marines are issued the rifle, while officers and NCOs are issued the carbine. A couple of the Bren-style LMG are mixed in for squad automatic use, while the Weapons Platoon receive the belt-fed LMG and MMG variants. During the first two weeks of combat, 33 malfunctions are reported, most being failures to feed, fire, eject, and extract. During one night ambush patrol, only one of the four Stoners works reliably. The culprits are determined to be the weapons' tight tolerances combined with the fine sand of the coastal plains in their Area of Operations. In response, Lima Company attempts to break-in their weapons with extended live-fire drills. For the most part, this plan succeeds, in conjunction with the delivery of a different production lot of ammo.

March: President Lyndon B. Johnson promises 25,000 M16 rifles to the Republic of Korea (South Korea).

The PMR office notes seven continuing issues with the M16A1: 1) Sources of alternate propellants; 2) High cyclic rates; 3) Chamber corrosion; 4) Barrel twist; 5) Fouling; 6) Tracer requirements; and 7) Product improvements.

The US Army completes distribution of the XM177E1 to troops in Vietnam.

The USMC asks Cadillac Gage to upgrade another eight of their early Stoner 63 to the 63A standard.

Mixed reports also come back concerning the XM148 grenade launcher. While M79 users quickly welcomed the rifle/grenade launcher concept, the XM148 proves completely unsatisfactory under combat conditions. Users complain that the quadrant sight was prone to snagging in brush, and worse, that the sight is difficult to use with any accuracy. Also listed as snag prone are the extended trigger and trigger bar. These can be bent or broken simply by opening or closing the rifle's receiver during/after fieldstripping. The separate cocking lever is quite unpopular due to the 30lb (~14kg) force required to cock the weapon. Within a few months, units with the XM148 are clamoring to have their M79 reissued. This is significant as most M79 users are only issued a M1911A1 pistol as backup for their grenade launcher.

384 Colt/Realist 3x scopes arrive in Vietnam for mounting on M16A1 rifles.

April: All live firing in Vietnam-oriented Army infantry training has been converted from the M14 to the M16A1 rifle.

Colt has made further improvements upon the XM177-series based upon feedback and suggestions from users. One such suggestion is lengthening the barrel so that the new Colt XM148 40mm grenade launcher can be mounted. The 1.5" longer barrel also has the additional benefit of improving the consistency of pressure curve at the gas port. In addition, Colt has developed an improved version of its "noise and flash suppressor." The new version can reportedly reduce the muzzle blast to that of the standard rifle. The longer barrel variant is type-classified the XM177E2. Negotiations begin for the procurement of 510 XM177E2 for the Studies and Observation Group (MACV-SOG).

Lima Company requests that the test period for their Stoners be extended by an additional month. This request is approved. However, the Bren-style LMG is removed from issue as being redundant.

The USMC places an order with Cadillac Gage for additional spare parts and ammunition linking devices to support the Stoner 63A.

All other USMC maneuver and reconnaissance units in Vietnam have been issued the M16A1.

May: The May 13th issue of Paris Match magazine publishes photos of dead Marines with field stripped (or otherwise hors de combat) M16A1. The photos were taken by French photo journalist Catherine Leroy during the recent battles for Hills 861 and 881 (North and South) near Khe Sanh (24 April-5 May 1967).

Two days after the Paris Match photos are published, the Ichord Subcommittee opens hearings on the M16. Appointed by Representative L. Mendel Rivers (D-SC), Chairman of the House Armed Services Committee, it is comprised of Representatives Richard Ichord (D-MI), Speedy O. Long (D-LA), and William G. Bray (R-IN).

A chrome-plated chamber is approved for the M16 rifle family. A fully chromed bore will not be approved until later.

The SEALs order an additional 36 Stoner 63A LMG. In contrast, the remainder of the Marines' Stoners are exchanged for M16A1 at the end of their test schedule.

Arthur Miller, Charles Dorchester, and George Sullivan receive US Patent #3,318,192 titled "Locked Action Rifle for Automatic and Semi-Automatic Selective Firing."

ACTIV publishes the report "XM148 Grenade Launcher." US Army Maneuver Battalions throughout Vietnam were sampled to record user reaction to, and experience with the weapon. Deficiencies of the XM148 were the poor position and projection of the sight, difficulty and unreliability in operation of the cocking and firing mechanism, unsatisfactory pointing and handling characteristics, slowness in loading, and degradation of mobility in some circumstances. Additional deficiencies were slow rate of fire, unreliability of functioning, and inadequacy of safety features. The XM148 is deemed unsatisfactory for further operational use in Vietnam. It is recommended that the XM148 grenade launcher be withdrawn from US Army Maneuver Battalions and that the M79 grenade launcher be reissued on an interim basis until an improved launcher or a new system is developed. Research and development activities should be continued on systems to provide soldiers in small combat units with the dual capability of point and area target destruction in a single individual weapon.

June: The Ichord Subcommittee visit Vietnam to examine M16 reliability issues first hand.

Retired Army Colonel E.B. Crossman files "Report of Investigation of M16 Rifle in Combat" with the Ichord Subcommittee. Comprised of 250 personal interviews with Army and Marine units in Vietnam, it reports that roughly 50% of the troops have experienced serious malfunctions with their XM16E1 rifle, of which 90% were failures to extract. The cause of these malfunctions was not determined.

Colonel Yount is relived of his duties as PMR.

WECOM sends a letter to commanders in South Vietnam detailing changes in recommended rifle lubrication.

Springfield Armory releases the report "Erosion Test on 5.56MM Rifle Barrels, Small Arms Weapon Study (SAWS)" Results are reported on limited erosion testing of three barrels each fabricated from AISI/SAE 4150 steel and Cr-Mo-V steel, with and without chromium plated bores. Tabulated test data include projectile velocities, land and groove diameters, temperature versus time curves, and ammunition expenditures. The unplated 4150 steel barrels were rejected after approximately 1,900 rounds were fired at 60 shots per minute. Rejection was based upon the projectile instability criterion, exceeding 15-degree yaw. The chromium plated 4150, and the unplated and chromium plated Cr-Mo-V barrels withstood 3,600 rounds fired at rates of 60 and 80 shots per minute.

Springfield Armory also publishes the report "Development of a Stellite-Lined, Chromium-Plated Barrel for 5.56MM Machine Gun."

Colt's Robert Fremont files patent applications for a partially curved 30 round magazine and a disposable plastic magazine.

US Army - Republic of Vietnam (USARV) issues ENSURE #77 requesting M16A1 sound suppressors. The Human Engineering Laboratory (HEL) at Aberdeen produces the models in question. (ENSURE: Expediting Non-standard Urgent Requirements for Equipment)

A private research firm, Planning Research Corporation, files a report claiming that given sufficient development a SPIW would be more cost-effective than other available infantry small arms. It recommends that the AAI SPIW rifle and DBCATA be chosen for further development.

The brief "Six-Day War" leaves Israel troops unimpressed by the reliability of their FN FAL and FALO. Testing for a new rifle begins. After testing the M16A1, Stoner 63, HK 33, and others, it becomes clear that nothing matches the reliability of their Arab enemies' Kalashnikov rifles. IMI sets about to create an improved clone. With the assistance of Interarms and Valmet of Finland, Israeli Galili and Yaacov Lior combine Valmet M62 receivers, Colt barrel blanks, FAL folding stocks, and a modified Stoner 63 rifle magazine to create the Galil.

FN builds a pair of 40mm grenade launcher prototypes for the CAL.

June-July: The US Army finally obtains the manufacturing rights and the TDP for the M16 and XM177-family. This is necessary for the establishment of additional production sources. Colt employees promptly prove the Army's point by starting a two-month strike in protest.

July: Thirty XM177E1 barrels with chrome-plated chambers arrive in Vietnam.

A draft of the US Army Small Arms Program (ARSAP) is published.

Lake City begins development of a steel 5.56mm cartridge case.

The US Army briefs representatives from private industry concerning what was to be later titled the Grenade Launcher Attachment Development (GLAD) Program. This briefing is intended to solicit interest in the development of alternative grenade launchers to the XM148. Out of 17 companies, only seven express interest.

FN submits a CAL prototype to Sweden for testing.

August: LTC Robert C. Engle assumes the position of PMR.

Yet another batch of comparison testing is conducted between 1-in-12" and 1-in-14" twist barrels. 2,000 new M16A1 rifles are used, evenly divided as to the installed barrel's rate of twist. The 1-in-14" barrels exhibit double the average extreme spread of the 1-in-12" barrels at 100m.

The US Army establishes case hardness standards for the 5.56mm.

CDCEC publishes "Infantry Rifle Unit Study (IRUS-75)."

The PMR Office distributes a fact sheet titled "Chamber Brush--M16A1 Rifle."

August-September: A multi-service field survey is conducted. Out of 2,100 troops interviewed, only 38 wished to trade in their M16 rifles. Of these, 35 wanted an XM177-variant.

September: All new production M16 rifles and spare barrels are now manufactured with chromed chambers.

The OCSA sends a memo to Secretary Resor titled "M16 Rifle Testing." Inside are the results of the first full scale-testing of the Sturtevant buffer.

LTC Robert C. Engle is replaced as PMR by Colonel Alvin C. Isaacs.

ACTIV publishes the report "CAR-15 Submachine Gun (XM177E1)." An evaluation of the CAR-15 Submachine Gun (XM177E1) was conducted at the request of the Office of the Assistant Chief of Staff for Force Development and Headquarters, US Army, Vietnam. The purpose of the evaluation was to determine the employment and performance of the XM177E1 in combat, assess its suitability for use in Vietnam, and to recommend a Basis of Issue. Major combat unit throughout Vietnam were surveyed through interviews, questionnaires, and special reports. Data on user experience, opinion, recommendations, and suggestions were recorded and analyzed. The XM177E1 was found to be reliable and durable, with no major deficiencies. It is deemed suitable for extensive employment in Vietnam. Combat leaders and their troops at all levels desire the weapon. The report recommends that: 1) The XM177E1 be issued as a standard weapon in Vietnam; 2) The M3 SMG be eliminated from the Army's inventory; and 3) Combat Developments Command develop a Basis of Issue plan by TOE line number.

Only three out of 17 firms are awarded GLAD contracts: Philco-Ford, Aero Jet General, and the AAI Corporation. Each of the contract winners offers a different approach. Aero Jet submits a bulky SPIW-type semi-automatic launcher. Philco-Ford offers a single shot launcher with a barrel that swings open to either side. AAI's single shot prototype is a forward opening, pump action design. Significant by its absence in the contract award is Colt, who has by this point delivered 27,400 XM148.

AAI begins in-house trials in support of their SPIW improvement program. Real progress has been made in extending functional reliability. However, the pre-existing issue of rapid heating as surfaced with actual occurrences of cartridge cook-offs. Ironically, the prototypes had never managed to function long enough to experience this problem in the past.

Fall: Colt makes a connection between gas tube fouling and calcium carbonate levels in WC846.

October: The Ichord Subcommittee releases its 600-page report. The US Army and Department of Defense (DOD) are faulted on a total of 31 points. Some of the primary criticism include the use of ball powder, hinting that Olin Mathieson's WC846 was given contract preference over DuPont's IMR powders, misinterpreting Olin's "sole source" status. (Olin owns the rights to "ball powder." However, Olin was not the Army's only source of gunpowder. It just so happened that no one less managed to develop an alternate powder which would reliably meet the velocity/chamber pressure spec for M193.) In addition, Army sponsored modifications are blamed for malfunctions, delays, and cost increases. This includes the introduction of new buffers and the recent decision to chrome plate chambers. The effects of OSD interference are not mentioned.

Twenty firms attend a pre-solicitation conference for M16/XM177 second sourcing. Only nine make the $1,000 bid deposit to receive a copy of the TDP and two M16A1 rifles.

Colt's Robert Roy receives US Patent #3,348,328 titled "Adjustable Buttstock Assembly."

Aberdeen's BRL publishes "The Lethality of a Bullet as a Function of its Geometry." From a set of formulae, the author concludes that the M193 projectile could be made to yaw more readily if the cylindrical section behind the cannelure were shortened.

Frankford Arsenal publishes the report "Metallurgical Analysis of 5.56MM Bullet, Copper Plated-Lead Cored." Samples of 5.56mm bullets, copper coated and lead cored, representing two production lots (lots A and B), were analyzed. The purpose of the analysis was to ascertain metallurgical properties and characteristics of each lot which relate to quality and possibly to method of manufacture. The testing procedures included chemical, metallographical, electron micro-probe, and hardness analyses. The results indicated that the electroplating quality of Lot B was superior to that of Lot A, especially with respect to adhesion and strength of coating. The electroplating techniques used in the manufacture of each lot were different as evidenced by Lot A having one continuous layer of copper and Lot B having a banded structure of three distinct layers of copper.

On behalf of the US Army, Stanley Silsby receives US Patent #3,345,771 titled "High Capacity Magazine and Cooperating Firearm Structure."

November: The US Army Chief of Staff orders an "intensive review" of Army management practices related to M16 product improvements. The DOD's Weapons System Evaluation Group (WSEG) with the assistance of the Army-funded Institute for Defense Analyses (IDA) prepares for yet another operational trial of the M16.

The "M16A1 Rifle System Test Coordinating Team" is established at Frankford Arsenal. Its job is to investigate ammunition performance and its relationship to M16 rifle function.

Colt's Kanemitsu (Koni) Ito files a patent application for a magazine dimension 'Go-No Go' field gauge.

Colt's George Curtis and Henry Tatro begin work on the CMG-2.

AAI begins a second set of in-house SPIW trials now concentrating on eliminating the cook-off problem.

December: WC846 is withdrawn for use in loading M196 tracer cartridges. WC846 is replaced by DuPont's IMR 8208M (formerly EX 8208-4).

Three additional firms place bid deposits for the M16 TDP, while four of the original bidders withdraw.

Frankford Arsenal releases the report "Fouling Test Investigation of 5.56MM Ammunition/Weapon System."

IWK's Ludwig Six and Rudolf Niemann file a US patent application for the design of a heavyweight 5.56mm projectile.

CETME's Dr. Günther Voss receives US Patent #3,357,357 titled "Rifle Bullet."

Colt's Henry Into files a patent application for the design of the CGL-5 grenade launcher.

William C. Davis sends a memo to COL Isaacs titled "Redirection of SPIW Program to Caseless Ammunition."

1968...

The SEALs discover a serious quirk with their Stoners: the "spin-back" jam. When in the belt-fed configuration, the Stoner ejects to the left. However, the 63A also feeds the belt from the left side. Occasionally, an ejected case will hit the drum or belt, and "spin-back" into the ejection port, causing a malfunction. On a positive note, Cadillac Gage introduces several enhancements, the most popular a short LMG barrel. This removes 6.25" in length and drops 1.56 pounds from the standard LMG barrel. Equipped with the new barrel, the LMG becomes known as the "Commando" model.

Beretta and SIG part ways on the 5.56mm rifle project over SIG Director Rudolf Amsler's insistence on using roller locking. SIG goes on to produce their SG530-1, a gas operated, roller locked design. At Beretta, Giuseppe Mazzetti, Leandro Zerneri, and Vittorio Valle set to work on a more conventional gas operated, rotary bolt design. The resulting design becomes the AR70. Both rifles still bear a fairly similar profile.

Colt switches from 6061 T6 aluminum forgings to 7075 T6 aluminum forgings upon suggestion by Gene Stoner. The earlier forging were found to be prone to intergranular exfoliation in the humid climate of Vietnam. Thin areas of the receiver, such as the area around the front pivot pin hole, could completely corrode apart within as little as three months.

L. James Sullivan leaves Ruger for Hughes Advanced Armament.

Frankford Arsenal begins experiments with the Low Noise Duplex Cartridge (LNDC). The earliest cartridges are loaded with a pair of 110gr tungsten core slugs. The initial projectiles use a blunt round-nose profile, but later efforts consist of a semi-spitzer shape.

Nosler continues to test its solid steel projectiles, now loading them in a .22-250.

Frankford Arsenal discovers that some cartridges shipped to South Vietnam have unusually soft cases.

January: The US Army Assistant Chief of Staff for Force Development (ACSFOR) creates the Army Small Arms Program (ARSAP) to handle all small arms projects. Nearly fifty projects are sorted into four major time spans: Continuing, Immediate (up to five years), Mid-term (up to 1980), and Long-term (up to 1990). The development projects are appropriately designated the "Future Rifle Program" (FRP). This includes projects such as the SPIW, now renamed the Serial Fléchette Rifle (SFR), the micro-caliber Serial Bullet Rifle (SBR), and other experimental cartridge concepts such as multiple fléchette loadings and caseless ammunition.

WSEG testing begins at Fort Sherman in Panama. 522 Marines test M16A1 rifles using new buffers and a mix of chromed and unchromed chambers with a mix of ammo from ball and IMR-loaded lots. M14 rifles were used as control. Ironically, M193 ball ammunition loaded with IMR 8208M exhibits the highest malfunction rates. IMR 8208M-loaded lots of M193 are suspended for use except for training. Its use in M196 tracer rounds continues.

The Secretary of Defense directs that until further notice no 5.56 mm ammunition loaded with extruded propellant be manufactured, or distributed in Vietnam.

Another field survey of troops armed with the M16 rifle is begun. It is part of a review of the M16 program presently being prepared by the Office of the Chief of Staff of the US Army. The purpose of the survey is to evaluate measures already undertaken to improve M16 reliability, to identify any current rifle problems, and to determine the general performance and acceptability of the system under combat conditions. All major Army units in USARV and one Marine Division were included in the survey sample. Two means are used to collect data: personal interviews and a questionnaire.

Colt's Foster Sturtevant receives US Patent #3,366,011 titled "Buffer Assembly Having a Plurality of Inertial Masses Acting in Delayed Sequence to Oppose Bolt Rebound."

The first 120 "Noise Suppressor HEL M4" arrive in Vietnam. These require the installation of a special bolt carrier and an add-on gas deflector.

FN submits a CAL prototype to the Belgian military for testing.

AAI publishes the report "5.56 MM Caseless Rifle Study." The objective of the program has been the development of a concept for an individual shoulder fired weapon capable of firing 5.56mm molded caseless propellant cartridges. The weapon concept shall be lightweight, gas-operated, and possess a selective semi and full automatic fire capability. The six month program consisted of a detailed engineering design and theoretical analysis; and the fabrication and testing of an experimental firing fixture. This program has demonstrated the feasibility of using the firing pin actuated mechanism as a simple and effective means of firing caseless ammunition.

Winchester's Joseph A. Badali and James H. Johnson receive US Patent #3,365,828 titled "Grenade Launcher for Attachment to a Rifle."

February: The full conversion from the M14 to the M16A1 rifle in Army training is approved subject to the gradual availability of weapons following priority shipment to Vietnam.

The DOD's Institute for Defense Analysis publishes "Study of the M16 Rifle System."

The DOD's Department of Defense Research & Engineering (DDR&E) publishes a rebuttal to the Ichord report: "Appraisal of the M16 Rifle Program."

On contract to the US Army, Comprehensive Designers, Inc. (CDI) studies the tolerance relationships in Colt's TDP for the M16/XM177. 140 areas of potential interference are found and reported to Colt along with the bidders for the second source contracts.

Frankford Arsenal releases the report "Special Tests of 5.56mm Ammunition." It is comprised of the results from ten tests using 150 new M16A1 rifles and 420,000 rounds of ammunition. Before testing, the chamber dimensions of all 150 rifles are checked in seven areas. Depending on the exact point of measurement, up to 77.5% of the rifle chambers were out of spec.

"Operational Reliability Test M-16A1 Rifle System, WSEG Report 124" on the Panamanian trials is classified and sealed by the OSD. This is suspected to be result of WC846's superior showing over IMR 8208M, which directly contradicted the allegations of the Ichord report.

Aberdeen's D&PS releases the reports "Final Report on Special Study of High Temperature Bore Fouling of 5.56-MM, M196 Tracer Cartridge in M16A1 Rifle" and "Initial Production Test of Chrome-Plated Chambers for 5.56-MM, M16A1 Rifles."

The field survey of troops armed with the M16 rifle in Vietnam ends.

Aberdeen's BRL releases the report "SPIW Modes of Fire." The study investigates the most effective mode of aimed fire to engage linear and point targets with the rifle portion of the SPIW system. Basic test data were generated by a group of riflemen firing a total of approximately 23,000 rounds at different types of simulated targets. A supplementary phase of the report discusses the applicability to the SPIW of doctrine evolved for full automatic fire from other rifle systems. The report recommends that while the AAI's high cyclic rate burst mechanism might give a higher percentage of hits over its much lower cyclic rate in full-automatic mode, the rifle would probably gain in reliability by removing the burst mechanism and tuning the weapon for a single 'optimum' rate of full-auto fire.

Arthur Miller receives US Patent #3,369,316 titled "Apparatus for Mounting and Locking a Folding Stock on a Rifle."

March: General Motors Corporation's Hydramatic Division receives a sole source award for M16 rifle production. This award is quickly withdrawn.

Aberdeen's BRL releases the memorandum report "Accuracy of Rifle Fire: SPIW, M16A1, M14." These include the results of full automatic and burst mode accuracy testing at Fort Benning between the M16A1, M14, and AAI SPIW prototypes. Of note is the performance of the test M16A1 rifles, equipped with two round burst mechanisms. These are found to improve the hit probability over controlled automatic fire in the same weapon. The M16A1 also allows for the highest number of target engagements. Not surprisingly, the SPIW is found to be the easiest to control in automatic fire, and this produces the highest hit probability per target engaged. The M14, combined with either the standard M80 Ball or M198 Duplex, is found to give a higher hit probability per target engaged than the M16A1. With the M198 Duplex, the M14 is considered to be competitive with the SPIW, at least per target engagement.

General Electric submits a proposal to continue development of Springfield's orphaned SPIW. (GE's Armament Division was already renting portions of the Springfield Armory facility.)

April: Springfield Armory is officially closed. Of 480 employees, less than 20 members of the staff agree to transfer to Rock Island Arsenal. The remainder quit. (Richard Colby, designer of the Springfield SPIW, is hired by GE's Springfield office.)

Contracts are let with H&R (DAAF03-68-C-0045) and Hydramatic (DAAF03-68-C-0048) for 240,000 M16A1 rifles apiece. In response to grumbling by the other six bidders, the Ichord Subcommittee is reestablished and the Senate Preparedness Subcommittee establishes its own "Special M16 Rifle Subcommittee" chaired by Senator Howard Cannon (D-NV).

The USAIB publishes the report "Military Potential Test of Noise Suppressor, HEL, M4, for M16A1 Rifle." The purpose of the test was to evaluate the advantages and disadvantages of the noise suppressor in realistic operational exercises characteristic of Vietnam. Factors such as position disclosing effects, system functioning, durability, reliability, and maintenance were considered. Fifteen M16A1 rifles with noise suppressors attached were used to conduct this test. Fifteen standard M16A1 rifles were used for control purposes. There were no deficiencies found; however, three shortcomings were noted. The gas deflector failed to deflect all of the escaping gases from the firer's eyes; the ejection pattern of the M16A1 rifle with the noise suppressor attached caused the expended cartridge to strike the cheek of left-handed firers; and the malfunction rate of the test weapon was unusually high (primarily double feeding). It was concluded that the Noise Suppressor, HEL, M4, had military potential and accomplishes the purpose for which it was designed, i.e., to deceive observers located forward of the test weapon as to the location of the weapon when it is fired. It is recommended that the Noise Suppressor, HEL, M4, be considered as having military potential, and further development be directed toward correction of the shortcomings.

May: The report "M16 Rifle Survey in the Republic of Vietnam" is published. The survey indicates that the M16 rifle system is suitable for the war in Vietnam. Particularly desirable qualities are its high rate of fire and its light weight. However, failures to extract were still occurring with enough frequency to undermine confidence in the M16. Although troops generally preferred to carry the M16 in combat, some misgivings were entertained about its reliability. Introduction of the chromed chamber appears to have reduced the number of failures to extract, but this development has not been fielded long enough to permit adequate evaluation. The authors conclude that continued product improvement and user efforts will be required to improve reliability.

AAI and Philco-Ford deliver their grenade launcher prototypes. Colt attempts to provide a completely new 40mm grenade launcher, the CGL-5, designed by Henry A. Into. Colt offers 20 free samples for testing, but the US Army declines. Aberdeen's Materiel Testing Directorate begins testing the AAI and Philco-Ford prototypes alongside the DBCATA. The testing consists of velocity, accuracy, reliability, adverse conditions, ruggedness, and lubricant compatibility tests.

Rock Island Arsenal and Winchester/Western conduct testing on alternate gas systems for the M16 rifle.

FN's Ernest Vervier files a US patent application for the design of the CAL's removable three-round burst mechanism.

June: Contract DAAF03-69-0021 is let to Colt for 740,803 M16A1 and 1,000 M16 rifles. 135,001 of the ordered M16A1 are later requested to be manufactured as M16 instead. Colt also contracts to produce 1,000 30 round magazines for initial production testing. This contract also includes the Technical Data Package for their manufacture. Delivery is projected in 6.5 months.

Aberdeen's D&PS releases the report "Final Report on Product Improvement of Submachine Gun, 5.56-MM XM177E2." The product improved components of the test weapons were: chrome-plated chambers, buffer, 1-1/2 inch increased barrel length, Delrin charging-handle latch, hand-guard slip ring, cadmium-plated slip ring spring, shot-peened upper and lower receivers, nylon coated buttstock and release lever, and grenade launcher spacer (for attaching an XM148 grenade launcher). With the exception of the Delrin charging handle latch, durability of all the product improvements was satisfactory throughout the test. The chrome-plated chambers demonstrated improvement over nonplated chambers in reducing failures to extract and the hand-guard slip ring offers advantages over the previous design in ease of assembly and disassembly of hand-guards. Kinematics studies showed that the energy-absorbing characteristics of the urethane end cap on the buffer are subject to change under repetitive impacts, causing undesirably large variations in cyclic rate within a burst. Progressive build-up of fouling in the flash/sound suppressor during firing tends to increase muzzle flash and sound level and apparently has an adverse effect on bullet stability and flight. It was recommended that further development of the XM177E2 submachine gun buffer and noise/flash suppressor be accomplished, that the Delrin charging handle latch be considered unacceptable, and that the remaining product improvements under test be considered suitable for use on the XM177E2 submachine gun and, as appropriate, the M16A1 rifle.

The OCSA's Weapons Systems Analysis Directorate publishes the 12 volume report "Report of the M16 Rifle Review Panel." The individual titles are as follows:

  • History of the M16 Weapon System
  • Small Arms Test Policies and Procedures
  • Audit Trail and Analysis of M16A1 Weapon and Ammunition System Tests
  • Review and Analysis of M16 Rifle Training
  • Ammunition Development Program
  • Procurement Production and Distribution History of the AR15-M16-M16A1 Weapon System
  • Review and Analysis of M16 System Reliability
  • M16 Surveys in the Republic of Vietnam
  • Review and Analysis of the Army Organizational Structure and Management Practices
  • Audit Trail of Chief of Staff - Army Actions and Decisions Concerning the M16
  • The Army Small Arms Program
  • M16 Product Improvement Modifications
An 18-pound test fixture for the CMG-2 mechanism is completed.

Colt's Robert Roy receives US Patent #3,386,336 titled "Convertible Machine Gun for Right- and Left-Hand Cartridge Feed and Operation."

Aberdeen's BRL publishes the report "BRL Survey of the Army Caseless Ammunition Program." An in-depth review of the Small Arms Caseless Ammunition Program was conducted. The results of the review, determined from interviews with contractors and Government personnel, and from reviews of progress reports prepared by contractors show the current status of the Caseless Ammunition Program. The results of this study show that the Caseless Ammunition Program has not reached the concept formulation phase.

June-July: New sound suppressors, the Sionics MAW-A1 and a model from Frankford Arsenal, are tested for potential issue under ENSURE #77. The Sionics suppressor requires no modification other than the removal of the flash hider. During safety testing, a Teflon bushing melted only after the can temperature reached 1,000 degrees. In contrast, one of the Frankford designed cans bursts during automatic fire.

July: Aberdeen publishes the report "M16 Rifle System Reliability and Quality Assurance Evaluation." A comprehensive study of the reliability of the M16 Rifle was undertaken. The report contains an extensive analysis of statistical and engineering data to estimate the reliability characteristics of the M16 Rifle system, analyze factors affecting the reliability of the system (propellants, projectiles, ammunition lots, cyclic rate, cycle time, chrome chambering, cleaning, lubricating, mode of fire, magazines and environments), and to establish a sound technical base for other parts of the study indicated below. The report also includes an analysis of the pertinent specifications for the rifles, magazines and ammunition, with particular emphasis on the validity of the parameters, the tests, the standards, the statistical sampling plans, the criteria, and their compatibility with the requirements for a reliable rifle system. Basically, the M16 Rifle is deemed a reliable system. Although the M16 Rifle and the M14 Rifle are not comparable in design, weight, ballistic parameters, operating features and effectiveness, their reliability characteristics are approximately similar. The M16 Rifle is more reliable than the M14 Rifle during its initial life, but it is slightly more sensitive to environmental effects and maintenance. Although the M16 Rifle currently is reliable, the study indicates that there is appreciable potential for improvement.

Summer: Due to Japanese export restrictions on Howa-made AR-18, ArmaLite establishes their own production line for the AR-18 at their facility in Costa Mesa, CA.

August: The AR-15/M16 Technical Coordinating Committee (TCC) is disbanded. The US Army Chief of Staff creates the US Army Small Arms Systems Agency (USASASA) at Aberdeen to manage research and development efforts related to individual and crew-served weapons up to .60 caliber. This includes the Army Small Arms Program (ARSAP), but not the PMR's office. Other responsibilities included infantry grenade launchers (but not the GLAD project), sight and fire control systems (but not electronic night sights and GLAD sights), and all related ammunition programs (except for 40mm grenades and those cartridges controlled by the PMR.)

At Frankford Arsenal, Lawrence Moore files the report "Gas Tube Fouling Characteristics of M193 Ball Cartridges in M16A1 Rifle."

At Colt, work begins on an actual CMG-2 prototype.

Aberdeen's Materiel Testing Directorate ends testing of the 40mm grenade launchers.

A letter contract is awarded to AAI for their grenade launcher design. It is unanimously selected based on its performance and cost.

Major Francis B. Conway, Commanding Officer of the US Army's Marksmanship Training Unit (MTU), supervises accuracy testing of the Sionics and HEL suppressors. The Sionics equipped rifle actually improved in 100m and 300m accuracy over the same rifle equipped with the standard flash suppressor. The HEL M4 suppressor did well at 100m but fell back at 300m. In spite of this, a modified HEL suppressor, the M4A, is pressed ahead for issue.

September: Aberdeen's BRL publishes the report "Launch Characteristics of the M-193 (Ball) and M-196 (Tracer) Projectiles from the XM177E2 Submachine Gun."

The USAIB publishes the report "Military Potential Test of Noise Suppressors for M16A1 Rifle." The purpose of this test was to evaluate the advantages and disadvantages of the test items with respect to such factors as: accuracy; position disclosing effects; system functioning; durability, reliability, and maintenance; and to select a device suitable for a Vietnam field evaluation and/or further development. Seven types of noise suppressors were tested.

100 HEL M4A suppressors are shipped to Vietnam.

On behalf of the US Army, Warren W. Wells files a patent application for a metal reinforced, plastic M16 magazine.

Colt's John Jorczak and David Behrendt file a patent application for an auxiliary cartridge case extractor.

October: Aberdeen's BRL publishes "Comparison of the Exterior Ballistics of the M-193 Projectile when Launched from 1:12 In. and 1:14 In. Twist M16A1 Rifles."

Naval Weapons Center-China Lake modifies a limited number of M16A1 with side-mounted 'jungle slings' and integral cleaning kits. The latter is contained within a modified pistol grip and buttstock.

Production of 960 additional HEL M4A suppressors is transferred to Edgewood Arsenal.

Aberdeen's Materiel Testing Directorate releases the report "Engineer Design Test of 40-mm Grenade Launcher Attachments for M16A1 Rifle (GLAD)." The report concludes that the performance of the AAI launcher is superior to that of the Philco-Ford and DBCATA launchers. Additionally, it was found that the test launchers, irrespective of type, are detrimental to the functioning performance of the rifle to which they are attached. The firing of the launcher causes the operating parts of the rifle to recoil out of position, resulting in failures to fire and failures of the hammer to remain seated. On two occasions, the latter condition caused inadvertent firing of the rifle when an attached Philco-Ford launcher was fired.

AAI is awarded a letter contract for development of a Serial Fléchette Rifle (SFR). (SFR is the new name for the rifle component of the SPIW.)

AC Electronics-Defense Research Labs publishes the report "Study to Increase Gun Barrel Life by Plating the Bore with Tungsten." During testing contracted by the US Army, a 0.004 inch oversized .220 cal rifled gun barrel was plated with 0.002 inches of tungsten, restoring its original bore size. The plated barrel and an unplated standard barrel were test fired with 1500 rounds of .220 Swift. Less erosion was experienced over a shorter barrel length in the tungsten plated barrel than in the unplated barrel.

November: The AAI grenade launcher is type-classified as the XM203.

End-user comments indicate that Colt's modified "noise and flash suppressor" for the XM177E2 is prone to rapid fouling, reducing the efficiency of the sound suppression. It is also found that the M193 ball projectile is prone to excessive yaw once this fouling had progressed far enough. The effect on the XM196 tracer is even worse, occasionally leading to in-air breakup of the projectile. Most troubling is that cyclic rate problems caused by ball powder in the parent M16 rifle are even worse in the XM177 family. Colt estimates that a complete ballistic/kinematics study of the XM177E2 will take 6 months at a cost of $400,000. In response, the US Army suggests an in-house, 29 month, $635,000 R&D study. However, this proves to be straw that breaks the camel's back in regards to additional procurement.

The Human Resources Research Organization releases "Training Implications, Extended Field Test, Infantry Rifle Unit Study, IRUS - 75 (IRUS IIBX)."

The report "Noise Suppressor Assembly HEL E4A" is published.

December: Hydramatic delivers its first 100 rifles two weeks ahead of H&R. Two of the H&R rifles fail 6,000 round endurance testing, one to a cracked bolt and the other due to excessive failures to chamber.

Authorization is given for 600 XM203 to be assembled and sent to Vietnam for extended testing. The great irony is that after AAI completes this 600-launcher order, all further production contracts for M203 are awarded to Colt.

On behalf of the US Army, Harvey H. Friend files a patent application for a combined extractor/ejector for the Winchester/Springfield semi-auto grenade launcher attachment.

Frankford Arsenal publishes the report "Investigation of 5.56mm, Cartridge Lot LC-12387 in Standard 5.56mm, M16A1 Rifles."

1969...

Sionics loans the US Army 20 MAW-A1 suppressors for field trials in Vietnam.

Lake City begins production of M196 using GMCS jackets. This is discontinued years later due to complaints of barrel erosion.

Industries Valcartier Inc. (IVI) of Canada begins production of a 68 grain 5.56mm Ball cartridge. This and a companion 800m tracer are later designated XM287 Ball and XM288 Tracer by the US Army.

Frankford Arsenal begins a three-year development effort to create a viable aluminum cartridge case for 5.56mm cartridges. Frankford also publishes test results on the solid steel Nosler projectiles. They are considered insufficiently stable, but Frankford recommends that they be studied further for their low cost and ease of manufacture.

The Infantry School publishes "Analysis of Vietnam Weapons Questionnaires (M16A1 Rifle and Others)."

Cadillac Gage introduces a right-hand feed mechanism for the Stoner LMG, which replaces the feed cover and feed tray. However, the existing belt boxes are only configured for left-hand feed. Thus, work on an improved belt box begins, resulting in the definitive 100 round box.

The West German government awards individual contracts to Diehl, HK, and IWK for caseless ammunition and weapon research.

HK engineers Tilo Möller, Günter Kästner, Dieter Ketterer, and Ernst Wössner begin work on what becomes the caseless G11 rifle.

Colt's Henry Into begins work on what will later be dubbed the SCAMP.

January: Aberdeen files the report "Analysis of Consolidated Cyclic Rate Data for M16A1 Rifle."

Frankford Arsenal releases the report "A Study of the Effects of Cartridge Case Mouth Waterproofing Compound on Fouling in the 5.56MM, M16A1 Rifle."

Aberdeen's BRL publishes the report "A Comparative Evaluation of the 7.62MM and 5.56MM, G-3 Assault Rifles." A test was conducted with 7.62mm G3 and 5.56mm HK 33 Assault Rifles to evaluate and compare the kinematics, reliability, safety features, physical characteristics, recoil impulse, rates of fire, projectile velocities, muzzle motion and accuracy of the weapons. No serious problems were detected during the tests, and the reliability of the weapons was comparable.

The British MOD tests yet another AR-18, a Howa production model. The mud tests continue to pose problems for the design.

WECOM publicly announces its SFR contract award to AAI. GE is also issued a contract for revamping the Springfield SPIW.

Colt's John Jorczak files a patent application for an improved sight for an attached grenade launcher.

February: William C. Davis and James B. Ackley file the report "Results of a Dispersion Test of 2,000 1:12 and 1:14 Twist M16A1 Rifle Barrels."

Aberdeen's D&PS publishes the report "Comparison Tests of M16A1 Rifles."

March: Colt's Robert Fremont files a patent application for an improved magazine design which would prevent double-feeding of cartridges.

The SEALs request an official "Mark" number for their Stoner Commando LMG.

Testing firing begins for the completed CMG-2 prototype. Afterwards, Colt begins demonstrations for the US military.

Spring: In response to requests from SEAL Team Two for even higher magazine capacities, Colt delivers a prototype 50-round magazine. The magazine is fabricated from three 20-round magazines welded end to end. The design uses a special follower paired with a pair of constant-force springs. (This feature was designed by Navy engineers at Naval Weapons Laboratory (NWL) - Dahlgren.) 35 magazines are known to be made to this pattern for testing by the US Navy. However, their performance is considered to be poor. NWL-Dalhgren later designs a series of 50-rd magazines on its own.

April: 500 XM203 are sent to Vietnam for a three-month evaluation to determine its suitability for tactical use by US Army units. ACTIV distributes the launchers to the 1st, 4th, and 25th Infantry Division, the 101st Airborne Division (Airmobile), and the 11th Armored Cavalry Regiment.

Colt's Robert Fremont receives US Patent #3,440,751 titled "Firearm Box Magazine with Straight End and Intermediate Arcuate Portions."

William C. Davis and James B. Ackley file the report "An Investigation of Gas-Port Pressures for Two Lots of 5.56mm Ammunition Containing Two Different Types of Powder."

FN's Ernest Vervier receives US Patent #3,440,925 titled "Automatic Firearm with Burst Control Means."

On behalf of the US Army, Herman F. Hawthrone receives US Patent #3,437,039 titled "Multicharge Cartridge for Multibarrel Automatic Guns."

May: Aberdeen publishes the report "Combined Initial Production and Inspection Comparison Tests of M16A1 Rifles."

Remington publishes the report "Report, Feasibility Study to Investigate the Sensitivity of Certain Small Caliber Incendiary Type Bullets." Remington's study had been conducted on behalf of Aberdeen's BRL.

The report "Burst Control Selector M16" is published.

IWK's Ludwig Six and Rudolf Niemann receive US Patent #3,442,216 titled "Infantry Rifle Bullet."

Aberdeen's BRL publishes "Drag and Stability Properties of the XM144 Fléchette with Various Head Shapes." The drag and stability properties of a family of conical head fléchette are presented, with cone angles varying from 5 to 90 degrees. The data cover a range from Mach 2 to Mach 4, determined from free flight spark range tests. Limited results on a spike-nose configuration are also discussed.

June: The US government agrees in principle to establish a plant for the manufacture of M16 rifles in South Korea. In addition, the US will provide foreign military sales (FMS) credits to support production equipment, raw materials, technical assistance, construction, royalty fees, and training. Shortly after the US government's decision, Colt representatives begin negotiations with South Korean officials regarding a commercial licensing agreement. South Korea is eventually authorized 100 percent rifle manufacturing capability, involving 124 individual parts ranging from springs to buttstocks. In contrast, Colt's factory produces only around 12 parts in house, and the remaining components are subcontracted among 70 vendors.

The Naval Training Device Center publishes the report "Ballistic Tests on the M-16 Training Cartridge."

Colt's Henry Into and John Jorczak file a patent application for the trap-door buttstock.

WECOM designates the AAI SFR as the "XM19 Rifle, 5.6mm, Primer Activated Fléchette Firing." At Springfield, GE has redesigned their SPIW, eliminating 58 parts from the 1966 model. GE lobbies for development of fléchette cartridges based on the 5.56mm M193 cartridge case. This would allow them the option of producing either a SFR, a micro-caliber SBR, or even a standard 5.56x45mm weapon. GE even proposes necking the 5.56x45mm case out to 6mm, especially with the saboted ammunition types. The larger bore volume is cited as having the side benefit of reducing flash and blast, equivalent to an extra 5 inches of barrel length. Olin-Winchester chooses a separate path, developing multiple-fléchette cartridges. (Note: The intended grenade launcher attachment for the competing rifles is to be either the XM203 or the DBCATA.)

On behalf of the US Army, Stanley Silsby files a patent application for an improved version of the side-by-side magazine used by Springfield Armory's 2nd Gen. SPIW (AKA: The current GE SFR.)

Dale M. Davis files a patent application for the basic design of what will become the IMP.

July: The first competitive bidding for M16A1 rifles results in awards to Colt (DAAF03-70-C-0001) for 458,435 M16A1 and to Hydramatic (DAAF03-70-C-0002) for 229,217 M16A1.

Colt's Robert Fremont receives US Patent #3,453,762 titled "Disposable Magazine Having a Protective Cover and Follower Retaining Means."

AR-18 production begins at ArmaLite's Costa Mesa facility.

Representative Richard L. Ottinger (D-NY) writes the US Comptroller General concerning the General Accounting Office's (GAO) investigation of the Future Rifle Program, specifically the SPIW.

August: The US Army's Marksmanship Training Unit publishes the results of accuracy testing initiated by Colt. Three standard M16 have been pitted against a trio of heavy barrel M16 rifles. Three National Match M14 rifles are used as the control. At 300m, the heavy barrel M16 rifles produce an average group of 7.6" versus 12" from the issue M16 rifle. The M14-NM rifles average 6.4". The MTU reports the obvious superiority of the heavy barreled rifles over the standard M16 rifles. However, they recommend that a heavier bullet and faster rifling twist be investigated for M16 use at ranges exceeding 300m.

Frankford Arsenal publishes the report "M16 Gas Tube Fouling -- Composition, Properties, and Means of Elimination."

Aberdeen's BRL publishes "Terminal Behavior of the 5.56 mm M193 Ball Bullet in Soft Targets."

ACTIV files the report "XM203 Grenade Launcher Attachment Development." The evaluation finds that the XM203 is suitable for use by US Army units in Vietnam. During combat, personnel prefer to use the XM203 rather than the M79 because the M16/XM203 combo provides greater fire power and versatility. The battle sight and the quadrant sight are useful during training. However, the following changes need to be made:

  • Remove the front sling swivel;
  • Modify the trigger so the safety does not inadvertently slip to the safe position;
  • Modify the trigger guard so the firer's fingers will not be pinched between the trigger guard and the M16's magazine;
  • Checker the handgrip of the XM203 to give the firer better purchase when his hands become slippery;
  • Modify the sling for attachment to the front sight and buttplate;
  • Modify the handguard insert so it does not break when the firer tries to disengage it from the front;
It is recommended that the XM203 replace the M79, the modifications detailed be made, and that the quadrant sight be eliminated. The recommendation on adoption is accepted and the XM203 becomes the M203.

Debell and Richardson Inc. publish "Development of Plastic Disposable Magazine for XM16E1 Rifle." Following the preliminary design studies and material selection, three design concepts were carried into the pilot production stage and field tested. Work was done at the same time on ways to retain rounds in loaded magazines, and on the design and pilot production of a protective cover for loaded magazines.

On behalf of the US Army, Stanley Silsby files a patent application for yet another improved version of the side-by-side magazine used by Springfield Armory's 2nd Gen. SPIW (AKA: The current GE SFR.)

September: The maximum allowable level of calcium carbonate in ball powders is reduced from 1% to 0.25%.

October: Aberdeen publishes the report "Operational Reliability Study of M16A1 Rifle"

Aberdeen's BRL publishes the report "Deformation Characteristics of One Lot (LC SP412) of 5.56mm M-193 Ammunition." Physical measurements of the ammunition were taken before and after launch and the results compared on an individual basis. Rounds were launched at standard muzzle velocity, recovered and refired at a reduced velocity and compared with other rounds launched only at the same reduced velocity. Several before and after launch rounds were contour measured and comparisons were made on the shape of the projectile.

Frankford Arsenal publishes the report "Bullet-in-Bore Study of 5.56MM, Ball, M193 Cartridge and M16A1 Rifle." This test consisted of the firing of cartridges crimped to 100 pound average bullet pull (normal representative production value), 35 pound average bullet pull (minimum specification requirement) and uncrimped cartridges, all reassembled without propellant from each of two 5.56mm, ball, M193 cartridge lots (LC12507 and TW18310) in each of three M16A1 Rifles with varying records of rounds fired.

WECOM's Future Weapons Systems Division publishes the report "A Methodology for Choosing the Best Caliber for a Light Infantry Machinegun." The best caliber is taken to be that one which yields the greatest effective range under constraints on weapon recoil energy and system weight. For bullets and guns having a particular configuration, relationships are developed which express these constraints. Semi-empirical expressions for recoil energy and system weight are obtained as functions of caliber and muzzle velocity. When energy and weight are constrained, a feasible region is defined in the two-dimensional space of caliber and muzzle velocity. Within this feasible regions, the greatest effective range is found at the smallest caliber (and largest muzzle velocity.)

Aberdeen also publishes the report "Engineer Design Test of 20-Round Plastic Magazine for M16A1 Rifles." A series of engineering design tests was conducted on 20-round plastic magazines of 6-10 nylon with 50% fiberglass reinforcement, for the M16A1 rifle. Equal numbers of test and control magazines were subjected to a series of comparative evaluations to determine function performance characteristics and material durability at extreme and ambient range temperatures, and in adverse conditions of mud, sand, dust, and water. The test magazine material was also checked for compatibility with various nonstandard solvents and lubricants. A displacement time study was made of the magazines to determine cartridge positioning characteristics during firing. The test results reveal that the test magazine requires further design engineering to improve performance in adverse conditions and to increase material durability at low temperature.

November: Production of XM177-type weapons is deleted from the second-source contracts.

LTC Rex Wing replaces Colonel Alvin C. Isaacs as PMR.

The Army Logistics Management Center publishes "Analysis of Program Factor-Demand Relationships for M16 Rifle Parts." This report contains results of an empirical study of the relationship that exists between demand for parts of the M16 and rifle density or round expenditure. Actual demands from Vietnam and the actual monthly density and round expenditure in Vietnam for 1967 and 1968 are used in the analyses. Density appears to have no bearing on demand. Round expenditure seems to affect demand but the changes are not proportional. Moreover, forecasts of future round expenditure are not very reliable.

On behalf of the US Navy, Robert A. Leverance and Morrison B. Moore, III file a patent application for a lightweight, inexpensive sound suppressor for the M16 that is easily drained during amphibious operations.

December: Aberdeen files the report "Reliability Characteristics of the M16A1 and M14 Rifle Systems at Low Temperatures."

Colt's Kanemitsu (Koni) Ito receives US Patent #3,482,322 titled "Method for Preventing Malfunction of a Magazine Type Firearm and Gage for Conducting Same."

The US Army reports on tests of Colt's latest belt-fed LMG, the CMG-2. Despite using the 68 grain GX-6235, the CMG-2 was considered to not offer enough range or a high enough rate of fire.

The Stoner Commando LMG (w/ right-hand feed) is officially type classified by the US Navy as the "Gun, Machine, 5.56mm Mark 23 Mod 0." 48 of these are eventually procured.

The USAF awards a contract to Colt for the construction of four Individual Multi-Purpose Weapons (IMP), as a proposed air crew survival weapon. The original goals for the weapon are a "lethal" range of 100 meters, a weight of less than 1.5 pounds, a maximum length under 13," and a minimum magazine capacity of 7 rounds. Dale M. Davis of the USAF's Armament Laboratory (Elgin AFB) is responsible the stockless bullpup design which others dub an "arm gun." The best known examples of the GUU-4/P IMP are the technology demonstrators chambered in .221 Remington Fireball. However, experimental models are constructed in a couple of .30 caliber wildcats for suppressed use. These cartridges are based upon a slightly shortened .30 Carbine case and a shortened .221 Fireball case respectively (sort of a stubby forerunner to J.D. Jones' later Whisper experiments). There was also discussion of building different models in Frankford Arsenal's 4.32x45mm micro-caliber cartridge (.17 Remington), 7.62x51mm, and 5.56x45mm. (The latter idea is developed and marketed commercially years later by Mack Gwinn Sr. and Mack Gwinn Jr. as the Bushmaster pistol.)

1970...

Dr. Carten, still Chief of the Technical Evaluation Branch of the AMC's Research Development & Equipment Directorate, files the ironically named report "The M16 Rifle - A Case History." Carten pins the primary blame for M16 malfunctions on the lack of specifications for case hardness. (Somewhere along the line, Colt reduced the strength of the extractor spring to help prevent rim shear. After it was found that this caused its own problems, Colt introduced the rubber nub insert for the extractor spring.)

Frankford Arsenal publishes the report "M16 Rifle/Ammunition Malfunction Modeling."

Production of the XM177E2 ends.

CIS begins manufacture of M16S rifles in Singapore.

ArmaLite experiments with coated projectiles in hopes of reducing bore friction. The coating is a new process developed by Du-Kote. ArmaLite also introduces the compact AR-18S.

C4 booby-trapped 5.56mm cartridges are encountered in the Phu Yen province of Vietnam. One soldier is killed and another wounded in separate incidents. EOD personal confirmed the contents. (Note: Dean has sources which indicate that conventional rifle primers should not be sufficient to detonate C4. However, I am including this claim from David Hughes for future reference. If Hughes' claims are indeed genuine, perhaps the C4 acts as a bore obstruction for subsequent shots, inadvertently providing the desired destruction of the weapon.)

Recently transferred from the USASASA to the T.J. Rodman Laboratory (Rock Island), AAI's XM19 program continues to debug the design. Early in the year, the CDEC starts a new series of field experiments at Fort Ord using the XM19.

The British Director General Weapons (Army) instructs Royal Small Arms Factory (RSAF) Enfield to begin a two-year Preliminary Study to consider future replacements for the 7.62mm NATO cartridge and the L1A1 SLR. Calibers ranging from 4mm to 7.62mm are to be considered.

The West German Department of Defense completes a list of design criteria for a new combat rifle. These design criteria are as follows:

  • Total length of the weapon less than 750 mm
  • Total weight of weapon including 100 rounds under 4.5 kg
  • A minimum of 50 rounds on the weapon
  • Full performance even under adverse conditions
  • High hit probability in three round burst
  • An effective range without sight adjustment out to 300m
Spain restarts testing of the 4.6x36mm.

January: Olin admits that WC846's manufacturing tolerances have played a role in cartridge performance. WC846 best suited for use in the 5.56x45mm is at the opposite tolerance end from WC846 best suited for 7.62mm NATO cartridges. Other manufacturers were not made aware of the differences. Henceforth, WC846 suitable for 5.56x45mm is relabeled as WC844. The remainder of the WC846 tolerance range retains the WC846 label.

Fort Benning performs weather resistance testing on brass and steel cased cartridges. The cartridges are test fired after 30 days of exposure.

February: Frankford Arsenal releases the report "Elimination of Gas Tube Fouling in the M16A1 Rifle when using the M200 Blank Cartridge." The culprit turned out to be the use of a white lacquer used by Twin Cities Army Ammunition Plant to seal the crimp of the blank cartridge. The titanium dioxide pigment in the white lacquer caused the observed fouling. Frankford recommends that clear or organically dyed lacquers be substituted for future M200 production runs.

Frankford also releases the report "Metallurgical Examination of Fouled Gas Tube and Flash Suppressor from an M16A1 Rifle."

Aberdeen's BRL publishes the report "The Gas Flow in Gas-Operated Weapons." The theory presented here predicts the pressure history in the gas cylinder and the motion of the piston for a given pressure and temperature history in the barrel.

General Electric's Armament Department publishes "Proposal for Development of a Special Purpose Individual Weapon." This document covers their SFR/SBR developments to date. However, it appears that GE never receives any further funding to follow up on their recommendations, effecting shelving the revised GE/Springfield SPIW.

March: The Secretary of Defense, Melvin R. Laird, announces that all US troops assigned to NATO duties will be equipped with the M16/M16A1.

All US Army infantry training has been converted from the M14 to the M16A1 rifle.

In hopes of preventing rim shear, Lake City experiments with 5.56mm cartridges using a thicker rim (0.055" versus the standard 0.045")

The USAIB at Fort Benning and G.A. Gustafson at Aberdeen each file a report titled "Product Improvement Test of Cartridges, 5.56-MM, Assembled with Steel Cartridge Cases." The purpose of the test was to determine suitability of the 5.56-mm steel-cased cartridges to replace standard brass-cased cartridges, and to determine the physical and technical characteristics of the 5.56-mm steel-cased cartridges. Specific test phases to which the steel-cased cartridges were subjected were physical characteristics, safety, cartridge-weapon compatibility, adverse conditions (60-day open storage period), reliability, and human factors. There were no deficiencies and one shortcoming found: the susceptibility of the test cartridges to rust. There were 47 incidents of split cases out of 21,642 steel-cased rounds fired. However, these split cases did not adversely affect the operation of the weapons. There were 71 malfunctions with weapons firing control cartridges and 53 malfunctions with weapons firing test cartridges. All malfunctions, with the exception of three, were either weapon- or magazine-caused. The blast, flash, noise, and felt recoil produced by the test cartridges were comparable to those of the control cartridges. The test cartridges ejected farther to the rear and right than did the control cartridges. It was concluded that the steel-cased 5.56-mm cartridges are compatible with the M16A1 rifle and are suitable for US Army use under intermediate climatic conditions.

Navy Ammunition Depot-Crane requests samples of the Colt CMG-2 for testing.

April: Re-titled "Product Manager, Rifles," LTC Wing's responsibilities are limited to the M16A1, XM203, and related ammunition.

The US Navy type-classifies the 'Rifle, 5.56mm Mark 4 Mod 0.' This is a M16A1 modified for dedicated use with the HEL M4A suppressor (AKA: Mk 2 Mod 0 blast suppressor) and optimized for maritime operations by the SEALs. Most of the operating parts of the rifle are coated in Kal-Guard, a quarter-inch hole is drilled through the stock and buffer tube for drainage, and an O-ring is added to the end of the buffer assembly. The weapon can reportedly be carried to the depth of 200 feet without damage.

Frankford Arsenal releases the report "Experimental Study of the Flow Characteristics in the Gas Tube of the M16A1 Rifle"

Pier Carlo Beretta files an US patent application for the design of the AR70.

Colt's Henry Into receives US Patent #3,507,067 titled "Grenade Launcher Having a Rotatable Forwardly Sliding Barrel and Removable Firing Mechanism."

May: Shipments of M16A1 rifles to US Army NATO troops begin.

Frankford Arsenal releases the report "Evaluation of the 5.56mm Nosler Steel Bullet."

The GAO releases the report "Development and Cost of the Army's Special Purpose Individual Weapon System." It recommends that the US Army does not procure any further SPIW-type weapons until the cost of the ammunition can be reduced.

June: Aberdeen publishes the report "Initial Production Test of Magazine, 30-Round, for M16A1 Rifles."

Testing of the Colt CMG-2 begins at NAD-Crane.

The USAF's Marksmanship School releases the report "Evaluation of AR-18 Rifle."

Hughes' Morris Goldin files a patent application for the 'lockless' firearm principle.

July: The US Army approves an Advanced Development Objective for a new LMG, introducing the nomenclature "Squad Automatic Weapon." Development of an intermediate SAW cartridge begins. Initial work centers on cartridges based on the 5.56x45mm's case.

Remington provides prototype grenade blanks for launching the RAG-B ring airfoil grenade. These blanks are later standardized as the M755.

AAI publishes "Results of Engineering Study on SPIW Muzzle Device."

August: Frankford Arsenal publishes the report "Ballistic Evaluation of 5.56MM XM287 Ball (68 Grain) and Matching XM288 Tracer Cartridge for XM207 Machine Gun."

Testing of the Colt CMG-2 ends at NAD-Crane. After modifications are made, the three weapons are transferred to the SEALs for field testing.

October: A contract is let to Colt for 751,245 M16A1 and 2,300 M16 rifles (DAAF03-71-C-003).

Aberdeen releases the report "Military Potential Test of Short Range Cartridges, 5.56-mm Ball, 7.62-mm Ball, and 7.62-mm Tracer." The objectives of the test were to determine the safety of the cartridges when fired from the M14 and M16A1 rifles and the M60 machine gun, and to compare cartridge characteristics and performance with that stated in the descriptive brochure. The cartridges with their short-range capability were designed for the training of military troops. The test cartridges differed statistically from values given in the manufacturer's brochure in cartridge weight, projectile weight, propellant weight, cartridge length, and projectile length.

The British Armament Design Establishment (ADE) at RSAF Enfield creates a 5x44mm cartridge (roughly a .20/223 Remington). Since 1969, their experiments have centered around the '50s-era prototype EM-2 rifle with its 7x43mm cartridge case necked down to 6.25mm. The change is inspired by a West German study indicating that future ideal military calibers will be 5mm or smaller. The final adopted projectile requires a 1-in-5" twist. Existing AR-15, AR-18, and Stoner 63 rifles are converted to the new cartridge, including the belt fed Stoner 63 variant. Later, bullpup conversions of the AR-18 and Stoner 63 rifles are executed.

Olin's Winchester-Western Division publishes "Summary and Recommendations - Multiple Fléchette Weapon System Development Contract." Winchester reports that they have finalized a 9.53mm multiple fléchette cartridge with an aluminum cartridge case. The loadings include a standard four fléchette payload (4,240fps), a pair of 'ball' fléchette paired with a tracer, and even a specialized armor-piercing 'penetrator'. Despite pushing pressures of up to 75,000psi, the large bore volume limits this to a brief spike, allowing the aluminum cartridge case to remain intact.

November: The last production lot of the white lacquer sealed M200 is completed at Twin Cities.

Frankford Arsenal releases the report "Contribution of the 5.56MM, Ball M193 Cartridge Metal Components to Gas Tube Fouling in M16A1 Rifle."

The Institute for Defense Analyses publishes the report "Primer Selection for Small Arms Ammunition." The paper examines the arguments for and against the Army's prospective standardization of primers for 5.56mm ammunition. The question is essentially whether one manufacturer shall continue to use primers containing basic lead styphnate in primers for the 5.56mm cartridges that it produces at its own plant and at a Government-owned plant it operates or whether that manufacturer shall use primers containing normal lead styphnate, as do all the other six producers of these cartridges. Findings indicate that the continued use of basic lead styphnate would yield minor advantages in lower cost to the manufacturer, possibility in manufacturing safety, and in competitive environment, while standardization on normal lead styphnate would yield a minor advantage in primer performance and two significant advantages: a reduction in possible problems associated with future changes in cartridges and weapons and a reduction in the testing required.

On behalf of the US Army, Harvey H. Friend receives US Patent #3,538,635 titled "Combined Extractor and Ejector Mechanism for Automatic Grenade Launcher ."

December: WECOM's Systems Analysis Directorate publishes the report "Analysis of M16 Rifle Dispersion and Dimensional Data." An analysis of the M16 rifle barrel dimensions and dispersion was conducted. Dispersion prediction equations were obtained using several categories of dimensional data. A discriminating procedure was developed suitable for use by field troops to separate barrels with 'acceptable' dispersion from those 'not acceptable'. Depth-of-muzzle-penetration by the erosion gage was selected as the discriminating variable.

Frankford Arsenal publishes the report "Feasibility Study of Spin-Stabilized Subsonic Projectiles."

1971...

M16A1 rifles begin to ship with chromed bores and chambers. Previously, only the chambers were chromed.

ARES, Inc. is co-founded by Gene Stoner and Bob Bihun.

Remington commercially introduces the .17 Remington cartridge. (Oddly enough, H&R had already offered a production-custom line of bolt-action rifles chambered for the wildcat version of the cartridge.)

The Swiss introduce the 5.56x48mm Eiger, a cartridge roughly in size to the .22-250. It is intended for military rifle experiments.

Production of the Stoner 63A ends.

Hughes submits an unsolicited proposal to ARPA for a light machine gun using its proprietary 'chiclet' cartridges.

The USASASA produces the concept of a Dual Cycle Rifle (DCR), a weapon in which a burst is fired at a very high rate while feed and extraction occur at a fraction of the speed. The DCR is the brainchild of USASASA commander Colonel Raymond S. Isenson and Technical Director Leonard R. Ambrosini. Fifteen companies eventually submit proposals and two are accepted. Multiple barrel designs are rejected due to weight and bulk. The winning proposals instead apply revolver cannon technology: a single barrel combined with a multiple chamber cylinder. The cylinder is fed from a box magazine holding three individual rows of cartridges. During the feed cycle, the top three rounds are simultaneously stripped into individual chambers. One design uses an asymmetrical three-chamber cylinder while the other uses a symmetrical nine-chamber cylinder. By 1973, the prototypes reportedly achieve cyclic rates of ~4,500 rounds per minute in three-round bursts.

HK hedges its bets with the introduction of a more conventional micro-caliber rifle, the HK 36 (not to be confused with the later G36). Its 4.6x36mm cartridge is the product of the joint Spanish/German study. It is best known for its asymmetrical "Spoon-nose" projectile: the Löffelspitz. The Löffelspitz is the product of studies by CETME's Dr. Günther Voss to find methods to deliberately induce yaw once a projectile strikes flesh, while not adversely effecting its accuracy during flight

The 40mm M433 HEDP grenade cartridge is type-classified and standardized as Standard A.

The National Board for the Promotion of Rifle Practice (NBPRP) approves the M16 and the civilian Colt AR-15 for use in their rifle matches. (Rules and Regulations For National Matches: Change 2 to AR920-30)

January: The Commanding General of CONARC orders all major commands to field at least one M16A1 rifle team for the US Army's championships.

Aberdeen's BRL publishes the report "Sensitivity Study of Rifle Gas Systems." Results of a sensitivity study of the M16 rifle gas system are presented; this study is based on a simulation of rifle gas system operation developed in the BRL. The calculations indicate that thermodynamic variables in the bolt carrier cavity are only weakly sensitive to variations in the following parameters: pressure and temperature in the gun barrel when the bullet passes the port, friction in the duct flow, and frictional resistance to motion of the bolt carrier. The computational results are sensitive, however, to the chosen origin of time on the oscillogram showing barrel pressure at the port station. Graphs are presented for a typical round illustrating pressure, temperature, density, and piston motion histories for M16 and AR-18 rifle gas systems.

Aberdeen publishes the report "Product Improvement Test of Quadrant Sight for the M203 Grenade Launcher." The sight was inspected for physical characteristics, fired for accuracy, and subjected to high and low temperatures, and to ruggedness and lubricants and solvents compatibility tests. No deficiencies were encountered; four shortcomings, however, were experienced. Three shortcomings were similar to shortcomings on the present standard quadrant sight. It was concluded that over-all performance of the test sight was equal to that of the standard sight and that neither was correctly calibrated to impact grenades at the 300 and 375-meter ranges when using ammunition with a velocity level in the lower limit of acceptability for the M203 grenade launcher. It was recommended that action be taken to produce ammunition with a velocity level of 245 +/- 5 fps from the M203 launcher, or that the sight (test or standard) be recalibrated for 40mm ammunition in the lower limit of allowable velocity acceptability (235 fps).

Comprehensive Designers Inc. publishes the report "Limit Dimensional Study of the M203 Grenade Launcher, M16, M16A1 Rifles and Quadrant Sight Combinations."

February: Aberdeen's BRL publishes the report "A Compendium of Ballistic Properties of Projectiles of Possible Interest in Small Arms." The shapes cover a range of Length/Diameter ratios ranging from conventional bullets (approximately 3.5) to that of fléchette (approximately 20), and include such shapes as cones, cone cylinders, and cone flares. The ballistic properties are mapped over a range of calibers and projectile densities. A drag-reducing tracer is included as one of the prime design considerations as a means of reducing base drag.

Colt's John Jorczak and David Behrendt receive US Patent #3,564,950 titled "Cartridge Case Extractor Tool."

Carroll D. Childers and Joseph C. Monolo file "NWL Technical Report TR-2536" concerning the NWL-Dalhgren's third model 50-round magazine. The authors recommend that the magazine be adopted and issued one per every deployed SEAL Team member.

ARPA, in conjunction with USASASA, awards TRW Systems a contract to develop an infantry rifle which will require far less maintenance than the issue M16A1. Appropriately, the project is named the "Low Maintenance Rifle" (LMR). An engineering team led by Don Stoehr is assigned to the project. The final design uses a gas-operated, roller-locked action, and bears more than a slight resemblance to the German FG42 paratrooper rifle. Since the weapon fires full-automatic only from an open bolt, the LMR borrows the trigger housing of the M60 GPMG, itself an amalgamation of the FG42 rifle and MG42 GPMG. Besides the 5.56mm models, at least one prototype is chambered for the XM216 SPIW cartridge.

On behalf of Frankford Arsenal, Colt's Technik, Inc. publishes "Feasibility Study of Fléchette Fired from Rifled Barrel." In these experiments, saboted fléchette have been loaded into standard 5.56x45mm cases and fired through M16 rifles. Conceived as a low-cost way of testing different sabot/fléchette designs, the improved accuracy results cast doubt upon the existing SFR weapon and cartridge designs.

March: The US and South Korean governments sign the M16 coproduction Memorandum of Understanding (MOU), which specifies the total quantity of rifles authorized for production in South Korea. This total includes both complete rifles and rifle equivalents in spare parts. The MOU also authorizes $42 million in FMS credits, prohibits South Korea from transferring rifles or components to third parties without the consent of the US, and can be terminated only by mutual agreement. Licensing and technical assistance agreements are also signed by Colt and the ROK Ministry of National Defense. This implements the MOU, establishes royalty fees, and provides training, production know-how, and technical assistance.

Colt's John Jorczak receives US Patent #3,568,324 titled "Battlesight for an Auxiliary Projectile Launcher."

Spring: AAI submits an unsolicited proposal for the development of a plastic cased blank.

April: The Colt CMG-2 is submitted for Navy nomenclature assignment.

May: The Colt CMG-2 is officially designated 'Gun, Machine, 5.56 Millimeter, EX 27 Mod 0.'

HK's Tilo Möller and Dieter Ketterer file multiple US patent applications for the HK 36's carrying handle and integrated optic, trigger pack attachment, and ambidextrous charging handle.

Colt's Stanley Silsby files the report "Lightweight Rifle/Submachine Gun." The report details the design and fabrication of the four IMP prototypes for the USAF. Demonstrations proved the basic concept of utilizing the shooter's arm as the gunstock was not only feasible but exceeded expectations. Further efforts will be made to improve trigger pull, trigger guidance, pistol grip locking, the arm rest, sighting, and to modify the design for quantity production.

June: Rodman Laboratory publishes the report "Concepts of Single Shot Grenade Launchers Attached to an Infantry Rifle." The report discusses the initial phase of an in-house design activity for the development of a 30mm grenade launcher. The launcher work is one aspect of the total Future Rifle System Program. As such, the conceptual efforts were molded around many of the requirements of that program so as to produce a composite weapon system consisting of both area and point fire components. In a span of ten weeks, a team of five people produced 14 deserving concepts from more than 23 basic approaches. Out of these 14, two concepts were selected for further development and inclusion in the overall Future Rifle System Program. Detailed design activity is currently underway to translate these two concepts to firing hardware for a projected delivery date of Fall 1971.

HK's Tilo Möller and Dieter Ketterer file a US patent application for the HK 36's semi-integral magazine and loading system.

July: Reynolds Metals publishes the report "Development of Aluminum Alloys for Cartridge Cases." The study was aimed at developing an aluminum alloy suitable for use in a 5.56mm cartridge case. Two distinctly different types of properties were required. In the annealed condition, the alloy must have good formability, such that the many cup and draw operations can be readily performed without the introduction of defects. In the final heat treated condition the alloy must exhibit both high strength and toughness. Ideally, a yield strength of 80,000 PSI and a tear strength to-yield strength ratio of 1.5 were desired by the Sponsor. Such a combination of properties is not currently available in any known commercial alloy. Variations of the commercial alloys 7075, 7178, and 7001 were studied.

Aberdeen publishes the report "Product Improvement Test of 5.56-MM Gilding-Metal-Clad Steel-Jacketed Tracer Projectiles."

Frankford Arsenal begins computerized parametric design analyses to design a cartridge from scratch to meet the SAW requirements. The body diameter of the final 6x45mm cartridge case is just shy of the .25 Remington (.410" vs. .422"). There are also experiments with a 6x51mm cartridge using aluminum cases.

WECOM publishes the report "Chromium Plating of Caliber .17 (4.32mm) Barrels." Caliber .17 (4.32mm) barrel blanks were machined to the exterior contour of an M16 Rifle barrel. Attempts to chromium plate these barrels with conventional plating fixtures were unsuccessful because misalignment of the electrode caused discoloration and shading of the plating. Attempts to obtain satisfactory, chromium-plated bores by use of better electrode alignment with the conventional fixtures were also unsuccessful. A self-aligning rotating electrode fixture was fabricated, and a technique for chromium-plating the caliber .17 bore was established. With the use of the rotating electrode fixture, many of the problems were eliminated that were encountered with the conventional fixtures on the caliber .17 bore.

August: The Office of Product Manager, M16 Series Rifles is disbanded. The staff is reassigned within WECOM.

WECOM publishes the report "Procurement History and Analysis of M16 Rifle."

Aberdeen's BRL publishes the report "Comparison of a Theoretical and Experimental Study of the Gas System in the M16A1 Rifle."

"Military Characteristics for Plastic 5.56mm Blank Cartridge" is published.

Colt's Stanley Silsby files a patent application for a rate reducer for the IMP.

WECOM publishes the report "Evaluation of Experimental Drive Springs for the XM19 Rifle." Laboratory tests and a theoretical study were conducted to determine the optimum design for increasing the life of the XM19 drive spring. Spring endurance tests were conducted by the Research Directorate of the Weapons Laboratory at Rock Island. Fatigue properties of eight experimental drive spring designs were evaluated under simulated firing conditions. The experimental springs consisted of various materials and strand constructions of three, seven, or 14 wires. A theoretical study was performed by the University of Illinois under direction of the Research Directorate on the dynamic response of helical compression springs. Theoretical and experimental data were correlated and were in close agreement. It was determined from this investigation that of the eight experimental designs that were evaluated, the two-piece spring assembly was superior because it retained maximum loads at the completion of the endurance tests.

September: Stanley Silsby, on behalf of the US Army, receives US Patent #3,604,142 titled "Four-Stack Cartridge Magazine."

October: Colt's Henry Into files a patent application for the design of the SCAMP.

Dale M. Davis receives US Patent #3,611,872 titled "Lightweight Compact Rifle."

November: The US Army, through the Land Warfare Laboratory at Aberdeen, signs a contract with AAI for the development of their proposed plastic case blank.

Colt's Robert Fremont receives US Patent #3,619,929 titled "Magazine with Anti-Double-Feed Indentations in the Side Walls."

Colt's Henry Into and John Jorczak receive US Patent #3,618,248 titled "Buttstock Assembly with a Latchable Door for a Compartment Formed Therein."

Colt submits an unsolicited proposal to the US Army for the Small Caliber Machine Pistol (SCAMP). The Colt SCAMP fires a short .224" caliber proprietary cartridge known as the .22 SCAMP.

December: The Naval Training Device Center publishes the report "Clothing Penetration Tests for the M-16 Training Cartridge." The report indicates that trainees are not adequately protected against stray projectiles based on penetration tests for the M16 training cartridge.

Fairchild Industries' John F. Dealy and Michael W. York file a patent application for a low profile set of M16 sights that are viewed through the struts of the carrying handle.

Colt's George Curtis and Henry Tatro file patent applications for the design of the CMG-2.

Col. Raymond S. Isenson of the USASASA rejects Colt's SCAMP proposal as the US Army is reportedly experimenting with a parallel small arms program called the "Personal Defense Weapon" (PDW).

1972...

Rock Island's Small Arms Systems Laboratory is assigned development of a Firing Port Weapon (FPW) for the XM732 Mechanized Infantry Combat Vehicle (MICV).

The US Army awards a contract with the Honeywell Corporation's Ordnance Division (now part of Alliant Techsystems) for the development of a 30mm grenade cartridge to replace the existing 40x46mm. (The actual design is credited to Picatinny.)

Aberdeen discovers that M196 Tracer cartridges loaded with IMR 8208M is clocking lower than normal cyclic rates. WC844 is tested in an experimental batch of tracer, and the cyclic rates return to normal.

Frankford Arsenal conducts a test program to optimize the hardness gradient of the 5.56mm case.

Aberdeen publishes the report "Optimum Bullet Study." While the use of aerodynamic computations as a design basis for artillery shell has been well established, the information generated had not been on shapes (or in sizes) of obvious interest to the small arms designer. Further work was needed to establish a base of confidence in computing the behavior of small arms projectiles and this should be done in bullet sizes and subject to typical small arms systems constraints. In an effort to provide this more general design basis, several programs were generated within the BRL and later partially supported by other agencies, particularly AMSAA and USASASA.

Frankford Arsenal publishes the report "An Analysis of 5.56mm Aluminum Cartridge Case Burn-Through Phenomenon." This work was aimed at understanding the 'burn-through' problem that has impeded orderly engineering development and application of aluminum alloy cartridge cases in high-performance ammunition since the 1890's. It has been shown that a gas path through the wall of an aluminum case, and through which propellant gas can flow during the internal ballistic cycle, is a precursor to the 'burn-through' phenomenon. Solutions to this problem have been found that either prevent propellant gas flow through a path in the case that develops unintentionally during firing of the ammunition, or alter the effect of propellant gas flow through such a gas path. Since an engineering understanding of the 'burn-through' phenomenon is available, work is currently underway to demonstrate the feasibility of aluminum cartridge cases.

RSAF Enfield's preliminary study concludes. Not surprisingly, the ideal caliber chosen is 5mm, for use with both the IW and LSW. Unconventional technologies such as fléchette and caseless cartridges were deemed too technically difficult to master within the desired time frame. A bullpup configuration is preferred as it gives the desired reduction in size without resorting to folding/collapsible stocks. (The latter design concepts are deemed to lack rigidity, causing accuracy to suffer.) To increase first-shot hit probabilities, the weapons must also be equipped with an optical sight similar to the SUIT. Based on the recommendations, a General Staff Target (GST 3518) is written to give specifications and goals for the following two-year Feasibility Study.

For unknown motivations, the British ADE decides to rename their 5x44mm cartridge as the 4.85x44mm (based on the diameter of the barrel's lands).

HK introduces a 5.56mm box-fed LMG, the HK 13.

February: The US Army MTU prepares a lesson outline for the development of a National Match M16A1 rifle. Testing has indicated the superiority of a 1-in-9" twist heavy barrel over a 1-in-12" twist barrel of the same profile. Bullet weights as heavy as 70gr are also tested with handloads.

The US Coast Guard publishes the report "Evaluating of the M-16 Rifle as a Line-Throwing Gun." A M16 rifle was adapted to a line throwing gun using an inert Mecar grenade. The results of the test firings indicate that the M16 is an unacceptable line throwing device.

March: The US Army issues a "Material Need" document for a "Squad Automatic Weapon, Light Machine Gun." Development contracts for 6x45mm SAW prototypes are let to Maremont (Saco) and Ford Aerospace. A design team at the Rodman Laboratory develops their own candidate, the XM235. The goal is to procure a weapon that weighs no more than 20lbs when loaded with 200rds of ammo. In addition, any weapons not chambered for the 6mm SAW must provide a ball cartridge that can defeat a helmet at 800m and a tracer that remains visible beyond the same range. Gene Stoner has advised Cadillac Gage not to bother with adapting the Stoner 63 design to the new cartridge.

Andrew J. Grandy files a patent application for a 'folded path' cartridge.

April: Frankford Arsenal publishes the report "Investigation of a Low Noise Duplex Cartridge (LNDC)."

Frankford Arsenal also publishes "Firing Shock Measurements on the M16 Rifle."

In addition, Frankford Arsenal publishes the report "Compilation of Frankford Arsenal Memo Reports on 5.56mm AR15/M16 Rifle/Ammunition System (1963-1970)."

May: Aberdeen's BRL releases the report "A Technique for Quality Control of Piston Primer Ammunition." Sponsored by the USASASA, the study desired to find ways of improving the reliability of AAI's primer-actuated action.

June: ArmaLite ceases AR-18 production at Costa Mesa.

Stanley Silsby, on behalf of the US Army, receives US Patent #3,672,089 titled "Large Capacity Magazine."

July: WECOM publishes the report "Solid Lubricant Coatings Curable at 225 F-300 F." Experimental solid-film lubricant coatings based on urea-formaldehyde, epoxy-polyamide, epoxy-silane, alkyd-urea, melamine-acrylic, and epoxy-urea resins were formulated for use on the M16A1 rifle. These coatings are cured after being applied to the rifle, and thus low temperatures are needed so as not to adversely affect the rifle's strength. None of these coatings when cured at temperatures of 225-300F had antiwear or corrosion preventing properties comparable to the fully cured MIL-L-46010A type of solid lubricant coating now used. Of the experimental formulations tested, those based on the urea-formaldehyde and epoxy-silane resins gave the best results. However, with the addition of a curing agent, boron trifluoride monoethylamine complex, to a qualified MIL-L-46010A base, the product could be cured at 275F, and all test requirements could be satisfied.

Frankford Arsenal releases the report "Sealing of Sabot and Primer of XM645 Cartridge." Waterproof sealing of the sabot and primer of the XM645 Cartridge (SFR) was achieved using a pigmented resin-solvent formulation. Firing tests conducted on experimentally sealed rounds have given every indication that the seals are acceptable. Efforts to effect sealing of the sabot by means of commercially available dry-shrink or heat-shrink preformed plastic caps, or to mold caps having the desired wall thickness, were successful.

Pier Carlo Beretta receives US Patent #3,675,534 titled "Automatic Rifle."

Aberdeen publishes the report "Product Improvement Test of Modified Leaf Sight for M203 Grenade Launcher."

Abraham Flatau files a patent application for the Ring Airfoil Grenade (RAG).

August: Aberdeen publishes the report "Comparison Test of 5.56-MM Tracer Ammunition Loaded with IMR 8208M and Ball WC844 Propellant."

Due to bullet seating issues with the 4.85x44mm, the British ADE decide to elongate the case neck, creating the 4.85x49mm. Prototype ammo is created by reforming fired 5.56mm blank cartridges.

October: Frankford Arsenal releases the report "Effect of 5.56mm Primer Components on Ballistic Performance of the M16A1 Rifle/Ammunition System" As a result of previous testing at Frankford Arsenal, it was decided to conduct more extensive testing of 5.56 mm primers. A factorial experiment was conducted to determine the effects of these primers on interior ballistics for both ball and tracer ammunition. The primer mixture, the primer weight, and the conditioning temperature of the ammunition were varied to investigate their effects, individually and in conjunction with each other, on the cyclic rate of the M16 rifle, on the action time of the ammunition in the rifle, and on the velocity of the projectile. The results of this test show that within the limits tested, primer components did effect ballistic performance, but to a lesser degree than external factors such as the rifle used and the conditioning temperature of the ammunition.

Frankford Arsenal also publishes the report "Effect of Propellant Additives in Reducing Fouling and Erosion in the M16A1 Rifle."

WECOM publishes the report "New and Improved Rubber Compounds for Weapon Systems." The report notes that newly developed fluorosilicone rubber inserts significantly increased the service life of the M16A1 rifle extractor springs.

November: Frankford Arsenal releases the report "Aluminum Cartridge Case Feasibility Study Using the M16A1 Rifle with the 5.56mm Ball Ammunition as the Test Vehicle." Identification of the 'burn-through' problem associated with high-performance aluminum cartridge-cases was made as the result of studies to isolate the elements of this problem and relate these elements to the interior ballistic cycle of the M16Al rifle system. One practical solution (the flexible internal element) to this problem was found. This solution was coupled with improvements in mechanical performance of the aluminum case by new analytical design techniques, tougher high-strength aluminum alloy, and novel case processing techniques. With the different improvement combined, the feasibility of the aluminum cartridge case was demonstrated by test firing.

Frankford Arsenal also publishes the report "Investigation of the Piston Primer For Use in the XM645 Cartridge."

Aberdeen's BRL releases the report "Resume of Special Tests of the XM19 Rifle and XM645 Ammunition." These tests were to examine the causes of health related complaints made by troops testing the XM19. Reported aliments included severe nausea, inflammations, and even eye injuries, all apparently caused by particles from the fiberglass sabot of the fléchette cartridges.

Abe Flatau, Donald N. Olson, and Miles C. Miller file a patent application for a pair of non-lethal RAGs, one with a payload and the other without. These become known as the Soft RAG and the Sting RAG, respectively.

December: GE's Richard S. Rose and Burton P. Clark file a patent application for GE's version of the Dual Cycle Rifle. It uses an asymmetrical six-chamber cylinder. During its forward stroke, the central operating rod/bolt strips three rounds from the magazine while ejecting three spent cases. During the rearward stroke, three rounds are fired in sequence while three spent cases extracted from the other chambers.

Battelle Memorial Institute publishes the report "Research and Development on Coextrusion of Bimetallic .220 Swift and 25mm Gun Barrels." This was a research and development program on lined gun barrels directed toward selecting desirable barrel and liner material combinations, which will increase the life of barrels in rapid fire gun systems, and developing the fabrication processes for producing these barrels with a metallurgically bonded liner. Coextrusion was used as the method for producing the lined barrel stock. The program was divided into two parts with the first part directed toward producing lined .220 Swift barrels of selected material combinations for testing in the M60. A-286 steel was selected as the barrel material, and TZM, Mo-0.5Ti, L605, Ta-1 OW, and T-222 were selected as the liner materials for the barrels. All the liners coextruded with the barrel steel satisfactorily over a small mandrel except T-222. The four successfully coextruded combinations were fabricated into .220 Swift barrels with swaging being used to rifle the barrels.

Philco-Ford publishes the report "Development of an Electrochemical Machining Process for Rifling Lined Gun Barrels." A 16-month program was conducted to advance high performance gun barrel technology by developing an electrochemical machining process for rifling high performance barrel liner materials. A total of 15 electrolytes and numerous electrochemical machining parameters were evaluated in conducting electrochemical machinability studies on iron-nickel-base, nickel-base, and cobalt-base superalloys, and on refractory alloys of columbium, molybdenum, tantalum, and tungsten. Four materials (L-605, VM-103, CG-27, and alloy 718) were selected for electrochemical rifling and fabrication into .220 Swift barrel liners. The rifled liners were insulated externally and assembled into outer barrel jackets using a drawing process, thus producing insulated composite test barrels. A total of 12 MG3 test barrels, representing the four liner materials and three jacket materials (H-11, A-286, and Pyromet X-15), were fabricated and delivered to the USAF. The results of this program indicated that electrochemical machining is a feasible process for obtaining high quality and low cost rifling, and that extrapolation of this process to larger calibers appears feasible.

1973...

Twin Cities receives the first complete SCAMP production line. (SCAMP: Small Caliber Ammunition Modernization Program) The new production line includes high speed loading presses, with the goal of increasing cartridge production from 60-100rpm to 1,200rpm.

Frankford Arsenal contracts additional aluminum case testing to be performed by Thiokal Chemical Corporation. Frankford also develops an aluminum-cased blank cartridge, which Aberdeen finds to be equivalent in performance to the issue M200.

Gulf + Western Industries Inc. begins development of a plastic cased ball cartridge.

The US Army awards a rifle development contract to ARES, Inc. In return, Stoner creates the Future Assault Rifle Concept (FARC) prototype. Oddly enough, it is Stoner's first 5.56x45mm design that hasn't started life as an earlier 7.62mm NATO design.

After failed experiments involving conventionally arranged bolts, HK's G11 development team happen upon a solution for providing gas obturation with caseless cartridges. Their chamber and breech will rotate about an axis at a right angle to the barrel.

HK introduces a 5.56mm belt-fed LMG, the HK 23A1.

In one of the few export sales that Colt and the US State Department approve, CIS begins delivery of roughly 30,000 M16 rifles to Thailand.

R&D work begins on the Civil Disturbance Control System. It is based on non-lethal variants of Abe Flatau's Ring Airfoil Grenade (RAG).

January: The US Army CDC approves a material needs document for a Future Rifle System (FRS). In many ways, it is a restatement of the SPIW requirements, incorporating both point and area target capabilities. However, the FRS is opened up to more than the previous fléchette cartridge systems. Among the requirements: The ability to maintain a rate of fire of 540 rounds every six hours for an entire day (15 grenade firings during the same six hour period). The point fire cartridge must be 25% more likely to incapacitate than the M193 from the M16A1. It must have a 30-50% probability of hitting a kneeling target at ranges from 300-500 meters. The area fire cartridge must be smaller than 40mm, yet maintain the lethality and range of the larger cartridge. The loaded weight of both systems combined must be less than 9-11 pounds. The point fire weapon is to display a minimum MRBS of 1,000 for the first 10,000 rounds fired. The area fire weapon is to display a minimum MRBS of 500 for the first 5,000 rounds fired.

Hughes' Morris Goldin receives US Patent #3,713,240 titled "Lockless Firearm System."

February: The British ADE is at work developing a rifle design for their 4.85x49mm cartridge. The Project Leader is Col. John Weeks, and the rifle design team is led by Sydney Hance. (Hance had been chief design assistant for the EM-2 rifle.) The resulting IW and LSW are both equipped with separate, push-through selector and safety buttons. While the IW fires from the closed-bolt position in all modes, the LSW fires from a closed-bolt position only in semi-auto mode. 3 round burst and full-auto fire are from an open bolt position. In addition, at least one prototype is chambered in 5.56x45mm for comparison purposes.

NATO's Action Committee 225 (AC/225) Panel III, Subpanel 4 issues "Operational Requirement for Light Support Weapon."

March: The US Army's Arctic Test Center publishes the report "Product Improvement Test of Gilding Metal Clad Steel (GMCS) Jackets for 5.56MM Projectiles." The testing had been conducted on behalf of Frankford Arsenal.

TRW ceases development of the LMR.

Morris Goldin files a patent application for the design of the plastic-cased 'chiclet' cartridge.

April: Radway Green delivers the first purpose made 4.85x49mm cartridges.

Colt's Stanley Silsby receives US Patent #3,724,325 titled "Rate Reducer."

May: On behalf of the US Army, Warren W. Wells receives US Patent #3,732,643 titled "Cartridge Magazine."

Aberdeen's BRL releases the memorandum report "Analysis of Exhaust Gases from the XM-19 Rifle -- An Application of Gas Chromatography/Mass Spectroscopy." A technique combining gas chromatographic and mass spectrometric analysis was developed and applied to determine the chemical composition of gases resulting from firing the XM19 rifle with the XM645 fléchette round. Cyanogen, carbonyl sulfide, carbon monoxide, nitrous and nitric oxides were among the products detected.

The Israeli Defense Forces (IDF) issue its first batch of Galil rifles.

HK's Tilo Möller and Dieter Ketterer receive US Patent #3,731,417 titled "Firearms."

June: Frankford Arsenal publishes the report "A Limited Analysis of a New Ammunition Concept for Potential Future Rifle Application." This report concerns the FABRL "low-impulse" cartridge, created in a joint project between Frankford Arsenal and Aberdeen's Ballistic Research Laboratories (BRL). (While it is clear that the initials FABRL indicate the parent agencies, it is later explained away as: "Future Ammunition for Burst Rifle Launch.")

The original projectile shape chosen by the BRL is the "AR2 artillery shape"; however, this proves difficult to manufacture. A slightly shorter compromise projectile known as the "Von Korman" bullet is used instead. This projectile weighs 32 grains as manufactured. The idea is that if the long, low drag projectile is launched at the same velocity as the shorter 55gr M193 projectile, the two cartridges will exhibit in similar trajectories. The lighter projectile will also provide the side benefit of reducing recoil by a third in comparison to the M193. Testing indicates that the "low-impulse" FABRL cartridge could improve the average probability of incapacitation by 60% over the M193, between the ranges of 0 to 500 meters.

Since the lighter "Von Korman" projectile does not need as much propellant to reach the target velocity, it is realized that the FABRL cartridge case could be made shorter. Experiments with the shorter case leads to additional experiments with aluminum cases, achieving an overall cartridge weight of 87 grains versus the ~182 grain weight of the M193 cartridge.

MAS publicly introduces its new 5.56mm bullpup Fusil Automatique. This is better known as the FA MAS, or FAMAS.

HK's Tilo Möller and Dieter Ketterer receive US Patent #3,736,686 titled "Automatic Hand Firearm with Interchangeable Magazine."

July: The US Army Armament Command (ARMCOM) is created by combining Army Munitions Command (MUCOM) at Picatinny, the Army Ammunition Procurement and Supply Agency (APSA), WECOM, and USASASA.

Control of the SAW project is passed on to Rodman Laboratory.

Fairchild Industries' John F. Dealy and Michael W. York receive US Patent #3,742,636 titled "Firearm Having a Carrying Handle and Associated Rear Sight."

August: Frankford Arsenal publishes the report "An Analysis of Various Primer Vent Configurations in 5.56mm Ammunition." Statistical techniques were used to determine the ballistic effect of various primer vent configurations in 5.56mm ammunition. The results indicate that the 5.56mm standardized primer vent provides the most efficient ballistic system (i.e., the highest velocity-pressure ratio) of all vent configurations tested. Velocity, chamber pressure, action time, propellant ignition time, temperature coefficient of velocity, and the temperature coefficient of chamber pressure are all affected by a change in primer vent cross-sectional area.

Aberdeen publishes the report "Development Test III of Cartridge, 5.56-MM, Aluminum, Blank."

September: Frankford Arsenal publishes the report "Stress Corrosion Susceptibility of Aluminum Cartridge Cases." The report concerns the investigation of stress corrosion cracking of experimental aluminum cartridge cases in a 6 percent sodium chloride boiling solution. The 5.56mm cases were of 7475 aluminum alloy, tempered to T6 or T73 condition, and the empty cases were assembled with projectiles to represent the stressed condition of finished cartridges. Stresses applied to the mouth rim and neck of the cases were calculated from the interference (i.e., projectile diameter versus internal diameter of the case mouth and the case neck wall thickness.) For each of three calculated stress levels, a range of failure times was observed.

William B. Ruger and Harry H. Sefried, II file a patent application for the three-round burst mechanism of the AC556.

Colt's George Curtis and Henry Tatro receive US Patent #3,756,119 titled "Machine Gun."

Rodman Laboratory publishes the report "Rifle-Gas Launched Grenade Concept." The report describes a feasibility study on a novel approach for launching a 40mm grenade. The study was undertaken with the goal of conceiving and developing a future grenade launcher which would be applicable to the Future Rifle System Program. This program advocates a weapon system which is a combination of both a rifle (point fire) and a grenade launcher (area fire). To maximize integration of the launcher to the rifle design, it was theorized to utilize rifle propellant gases to launch a grenade projectile. The proposed concept would provide for reduced grenade ammunition costs, reduced number of launcher component parts, lighter total weapon system weight, and more grenade rounds per combat load. A concept which contained all of the above features was generated, designed, fabricated, and tested.

October: On behalf of the US Army, Leonard R. Ambrosini and Charles N. Bernstein file a patent application for the design of an external tracer projectile.

Frankford Arsenal publishes the report "Analytic Study of Extraction Forces in the M16 Weapon." A parametric study involving six geometric and materials parameters for both conventional brass and 7475 (TMT) aluminum 5.56 mm cases in the M16 weapon is presented. Results defining the lowering of extraction force in terms of six materials and design factors are stated. It is found, based on these results, that the aluminum case is superior to brass in ease of extraction.

Philco-Ford publishes the report "Process Development and Characterization of Chemical Vapor Deposited Tungsten for Gun Barrel Applications." A 20-month program was conducted to develop improved chemical vapor deposition (CVD ) processes for applying tungsten to the bores of gun barrels, and further, to characterize the physical and mechanical properties of the CVD tungsten as deposited. Conventional and high strain-rate tensile and compression tests were conducted on CVD tungsten as deposited on 4150 steel at temperatures of -65 F, ambient, and 200 F. Density, thermal expansion, and thermal conductance measurements were also made. Barrel materials of CG-27, L-605, 718, and Pyromet X-15 were also investigated. Based on test firings, acceptable CVD tungsten adherence was demonstrated on 4150, but the other four alloys revealed only marginal quality. Fourteen MG3 test barrels of the five materials (chambered in .220 Swift) were fabricated and delivered to the USAF.

November: Rodman Laboratory publishes the report "Effect on the M16Al Rifle of Firing .22 Caliber Ammunition." A 25,000 round test program was conducted to determine the effects on the M16Al Rifle of firing up to 10,000 rounds of .22 caliber rimfire ammunition through it. No significant, permanent degradation of the rifle was found.

Rodman Laboratory also publishes the report "Holographic Analysis of Small Arms Barrels." Double-pulse holography techniques were used to observe gun-barrel deformation and motion during firing. Radial barrel deformations of an M16 barrel of approximately 0.0002 inch were observed.

Colt's Henry Into receives US Patent #3,774,500 titled "Machine Pistol."

HK's Tilo Möller and Dieter Ketterer receive US Patent #3,774,498 titled "Charging Device for Automatic Firearms."

December: Rodman Laboratory publishes the report "M16A1 Rifle Accuracy Parameters." An accuracy test program was conducted to determine which factors if any limit the accuracy of the M16A1 Rifle, those factors being looseness of the weapon's components, lubrication, corrosion, mixing of different types of ammunition, and types of rests used.

Aberdeen publishes the report "Product Improvement Test of Cartridge, 5.56-MM, Ball, M193 with Gilding-Metal-Clad Steel-Jacketed Projectile."

ARMCOM removes fléchette cartridges from 'immediate consideration' for use in the Future Rifle System Program.

On behalf of the US Army, Robert F. Magardo, Leonard R. Ambrosini, and Raymond S. Isenson file a patent application for their version of the Dual Cycle Rifle.

HK's Tilo Möller and Dieter Ketterer receive US Patent #3,777,381 titled "Firearm Carrying Handle and Sight Protector."

Abe Flatau, Donald N. Olson, and Miles C. Miller file another patent application for the Soft RAG.

On behalf of the US Navy, Robert A. Leverance and Morrison B. Moore, III receive US Patent #3,776,093 titled "Muzzle Blast Suppressor."

(Next: 5.56mm 1974-1985)
by Daniel E. Watters, Small Arms Historian
Post questions or comments in The Gun Zone Forum.
© 2000-2007 by
The Gun Zone
All Rights Reserved.
Woolrich Elite Series TacticalTM is a Backyard Outfitter Exclusive.

This page, as with all pages in The Gun Zone, was designed with CSS, and displays at its best in a CSS1-compliant browser... which, sad to relate, yours is not. However, while much of the formatting may be "lost," due to the wonderful properties of CSS, this document should still be readable.