Japanese
5.5"/50 (14 cm) 3rd Year Type
14 cm/50 (5.5") 3rd Year Type
Updated 23 August 2007

This weapon was the standard secondary gun for most of Japan's capital ships built or planned between 1915 and 1922 and was the primary gun on light cruisers built prior to 1930.  It was also the most numerous coastal defense gun used during World War II.

This gun was adopted in 1914 as a replacement for earlier 6" (15.2 cm) guns as it was felt that the lighter shells were better suited for manual handling by the average Japanese crewman.

Redesignated in centimeters on 5 October 1917.

Earlier guns were built with four layers and wire-winding (Model No. II), but later guns were of built-up construction without the wire (Model No. IV).  Used Welin screw breech-blocks.

WNJAP_55-50_3ns_Yubari_pic.jpg

Light Cruiser IJN Yubari in November 1924
This cruiser had single 14 cm (5.5") mounts bow and stern with twin 14 cm (5.5") superfiring mounts above them
U.S. Naval Historical Center Photograph # 19-N-9957

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Click here for additional photographs
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Gun Characteristics
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Designation 5.5"/50 (14 cm) 3rd Year Type (Model 1914)
14 cm/50 (5.5") 3rd Year Type (Model 1914)
Ship Class Used On
(see Note)
Capital Ships:  Ise, Nagato, Amagi, Kaga, Kii and "13" classes
Carrier:  Hôshô
Cruisers:  Tenryû, Kuma, Nagara, Naka, Yubari and Katori classes
Seaplane Carrier:  Nisshin
Minelayer:  Okinoshima
Submarine Tenders:  Chôgei class
Date Of Design 1914
Date In Service about 1916
Gun Weight 5.5 - 5.6 tons (5,600 - 5,700 kg)
Gun Length oa 284.8 in (7.235 m)
Bore Length 275.6 in (7.000 m)
Rifling Length 235.0 in (5.968 m)
Grooves (42) 0.55 in deep x 0.252 in (1.40 mm x 6.40 mm)
Lands 0.160 in (4.07 mm)
Twist Uniform RH 1 in 28
Chamber Volume 1,404 in3 (23 dm3)
Rate Of Fire 6 to 10 rounds per minute, depending upon the rate of supply
Note:  Many of the capital ships listed above were cancelled, scrapped or converted to aircraft carriers as a result of the Washington Naval Limitation Treaty.  As a result, only the Ise and Nagato classes saw service with this weapon.
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Ammunition
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Type Bag
Projectile Types and Weights
(see Note 3)
Capped Common - 83.8 lbs. (38.0 kg)
Capped Common Mods 1 & 2 - 83.8 lbs. (38.0 kg)
Common Type 0 HE - 83.8 lbs. (38.0 kg)
Common Type 2 HE - 83.8 lbs. (38.0 kg)
ASW - 92.4 lbs. (42.0 kg)
Common Type 3 IS - 83.8 lbs. (38.0 kg)
Bursting Charge Capped Common - 4.4 lbs. (2.0 kg)
Capped Common Mods 1 & 2 - 4.4 lbs. (2.0 kg)
Common Type 0 - 6.3 lbs. (2.86 kg)
Common Type 2 - 5.7 lbs. (2.60 kg)
ASW - 6.3 lbs. (2.86 kg)
Projectile Length Capped Common Mods 1 & 2 - 21.65 in (55.0 cm)
Common Type 0 - 21.81 in (55.4 cm)
Common Type 2 - 21.81 in (55.4 cm)
ASW - 22.56 in (57.3 cm)

Others - N/A

Propellant Charge All except ASW
   22.8 lbs. (10.33 kg) 40C or 50C
   24.2 lbs. (10.97 kg) 37DC

ASW - N/A

Muzzle Velocity All except ASW - 2,789 to 2,805 fps (850 to 855 mps)
ASW - 820 fps (250 mps)
Working Pressure 18.4 to 18.5 tons/in2 (2,900 to 2,910 kg/cm2)
Approximate Barrel Life 500 - 600 Rounds
Ammunition stowage per gun N/A
Notes:

1) IS is my abbreviation for the Type 3 Common incendiary shrapnel round (sankaidan) intended for AA use.

2) The propellant charge was in one bag with a 2.1 oz (60 gm) black powder igniter.

3) Capped Common shells were introduced in 1916 and were replaced by Capped Common Mods 1 & 2 in 1934.  Common Type 4 was introduced in 1932 and was replaced by Common Type 0 in 1940.

4) The ASW projectile was flat nosed.  ASW rounds were issued in 1943 following extensive testing.  Penetration performance not available.

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Range
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Elevation With 83.8 lbs. (38.0 kg) HE Shell
Range @ 20 degrees 17,280 yards (15,800 m)
Range @ 25 degrees 19,140 yards (17,500 m)
Range @ 30 degrees 20,890 yards (19,100 m)
Range @ 35 degrees 22,500 yards (20,574 m)
Elevation With 92.4 lbs. (42.0 kg) ASW Shell
Range @ 40 degrees 4,590 yards (4,200 m)
Note:  Minimum range of ASW shell is given as 875 yards (800 m).  Ranges less than this tended to ricochet.
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Mount / Turret Data
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Designation Single casemate mounts
   Ise (20), Nagato (20), Kaga (20), Kii (16-20) and Amagi (16):  N/A

Single pedestal mounts
   Hôshô (4), Tenryû (4), Kuma (7), Nagara (7), Naka (7) and Yubari (2):  N/A

Twin Mounts
   Yubari (2), Okinoshima (2) and Jingei (2) Classes:  A1
   Katori (2) and Nisshin (3):  A2

Weight  Single Mounts:  About 20 tons (21 mt)

Twin Mounts:  About 36 tons (37 mt)

Elevation
(see Note 3)
Single Mounts

   Ise class:  As built:  -7 / +20 degrees.  Later:  -7 / +30 degrees
   Nagato class:  As built:  -7 / +25.  Later:  -7 / +35 degrees
   Tenryû class:  -7 / +20 degrees
   Kuma and Nagara classes:  -7 / +25 degrees
   Sendai and Yûbari classes:  -7 / +30 degrees

Twin Mounts
   Yubari, Jingei and Okinoshima:  -5 / +30 degrees
   Katori Class and Nisshin:  -5 / +35 degrees

Elevation Rate Single Mounts:  Manual operation, only

Twin Mounts:  6 degrees per second

Train Capital Ships:  About +70 / -70 

Light Cruisers:  +150 / -150 degrees

Train Rate Single Mounts:  Manual operation, only

Twin Mounts:  4 degrees per second

Gun recoil N/A
Loading Angle Any angle up to +20 degrees (hand ramming)
Notes:

1) Single mountings on cruisers had bucket chain hoists which brought both projectiles and propellant up to the weather deck.  All transfers to and from the magazines, hoists and guns were performed manually.

2) The Twin Mounting served as a model for those for the 12.7 cm/50 (5") guns used on the "Special" destroyers of the Fubuki class.

3) Gun elevation for the Ise class was increased during modernization in 1935.  Gun elevation for the Nagato class was increased during modernization in 1934.  During these refits, two guns were removed from all four of these ships.

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Data from
"Naval Weapons of World War Two" by John Campbell
"Japanese Cruisers of the Pacific War" by Eric Lacroix and Linton Wells II
"Cruisers of World War Two" by M.J. Whitley
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US Naval Technical Mission to Japan report O-19:  Japanese Projectiles General Types
US Naval Technical Mission to Japan report O-54(N):  Japanese Naval Guns