Why "ballistics by the inch"?  Well, just about forever people have wondered what kind of trade-off one made in choosing a gun with a short barrel - how much power were you giving up for convenience/concealability?  There has been a lot of anecdotal information available - comparing this 2" .38 to that 6" .38, or a longslide .45 to an officer's pistol with a shorter barrel - but there hasn't been much in the way of consistent research made available to the average gun owner.  In the 1980s American Rifleman did some tests using a .44 mag revolver, cutting the barrel down from 18" to 1", and back in the 1930s someone did something similar with a 30-30.  But just try and find that data quickly.  And further, how does that data compare to your 9mm or .32?  Do they all lose power at the same rate?  Are some ammos better for your purpose than others?

We were curious just exactly what the drop-off in velocity was for a given caliber over a range of barrel lengths, and using a variety of available ammunition.  So, we decided to do some actual testing.  And, we wanted to make this information freely available as a service to gun owners everywhere.  This website is the result.



Magazine Coverage

The April 2009 issue of Concealed Carry Magazine (the member's publication of the US Concealed Carry Association) contained a great article on the BBTI project.  With the permission of the editor, the entire article is available here in pdf format.

And the Nov/Dec 2010 issue of Concealed Carry Magazine contained an article on our expanded testing of the .380 cartridge.  Again, with the permission of the editor, the entire article is available here in pdf format.

Additional Testing

Also in April of 2009 we did an additional sequence of testing over 5 days, in response to comments and discussion of our initial testing data.  This came in two primary parts:  "chop tests" of three calibers - .327 Federal Magnum, .41 Magnum, and 10mm; and additional "real world gun" tests of more than 40 additional guns in the calibers we had originally tested, with a particular emphasis on carbine-length guns.  In both cases, all the same protocols as the initial tests were followed, and the data recorded and posted as previously.  Because of the large number of additional "real world guns" tested, we decided to create separate graphs for those guns in each caliber.

In August of 2010 we decided to do another run of tests, lasting three days, this time revisiting the .380 ACP cartridge, as well as first forays into the 9mm Makarov and 9mm Ultra.  We wanted to return to the .380 because it has become such a popular small self-defense cartridge and there are both new guns and new brands of ammunition available.  During this round of testing, we did "chop tests" for 8 different ammunitions (repeating two types tested previously) and then tested 12 "real world guns" (again, repeating two types tested previously).  Lastly, we did one set of tests for the new .327 magnum barrel for the Bond derringer, which has been added to the “real world” data for that page.


We'd like to thank Pat and the folks at Fin & Feather in Iowa City, as well as Dave & Lee at Powder Horn in Columbia.  Without their help in getting the ammo and equipment we needed, none of this would have been possible.  Likewise, thanks to our spouses, who were not just tolerant but enthusiastically supportive of this rather nutty project.

Additional Ballistics Resources

Our little project here is not the end-all of ballistics testing, just one more component available for the common good.  In addition to extensive discussion about ballistics to be found at many gun forums, here are some other great resources pertaining to ballistics testing you should check out:

    BrassFetcher:  excellent resource, with an emphasis on bullet performance in ballistic gelatin
    The Box O' Truth:  testing ammo penetration through various barriers

This project, and all of its results, is only our fault.  We (well, Jim K, mostly) paid for everything ourselves, and we did not receive any kind of sponsorship or remuneration from anyone.  We did all the work.  We used products we were either familiar with, or because they were what was available, and mentioning them by name does not constitute an endorsement of any kind.  Furthermore, the data is provided purely for entertainment purposes - to better facilitate arguments over what ammo or caliber or gun is "best."  How you use the data is entirely up to you.  And if you think you could do better, feel free to spend the money and do the work and publish your own results.  Or not.  Your choice.

Finally, while we did decide to test a range of different ammunitions, we realize that our tests are not comprehensive - we did not test every single type or brand of ammo available for a given caliber.  Indeed, it would be almost impossible to do so - manufacturers change formulation of the ammunition frequently, so any such comprehensive tests would be obsolete by the time they were done.

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