Revolver and the .45 GAP

Caleb spotted a fellow IDPA competitor using .45 GAP cartridges in a revolver! I had never heard of such a thing before.

The .45 GAP (Glock Auto Pistol) was designed to duplicate the .45 ACP ballistics but in a shorter cartridge more suited to high capacity semi automatics. It is the last thing I would have thought of using in a revolver, but the owner of the wheelgun had some good reasons.

.40 S&W (left) and .45 GAP

Steve Johnson

Founder and Dictator-In-Chief of TFB. A passionate gun owner, a shooting enthusiast and totally tacti-uncool. Favorite first date location: any gun range. Steve can be contacted here.


  • Komrad

    We did make a .45 acp and .45 colt revolver during WWII. It required the use of half moon clips for extraction of .45 acp brass. Early versions needed half moon clips to fire .45 acp later ones required a pencil or other rod to push .45 acp brass out if half moon clips were not used.

  • Have you seen the prices on 45 GAP ammunition? Ouch!! It’s a cool round, but the ammunition is expensive to shoot and often difficult to find.

    • Heath, yep, thats why I would not buy a .45 gap pistol.

  • PaulMcM

    Generally speaking, the farther the bullet has to jump from the revolver’s chamber to the barrel’s forcing cone, the less accurate the cartridge will be.

    But, if you really want a shorter cartridge you can either: 1) seat the bullet deeper in the case (adjusting load accordingly); or 2) trim your .45 acp brass shorter. Solution #1 is already being used by many cowboy action shooters who are using .45 LC with very light powder loads and the bullets seated very deep in the case.

    The author also suggests that small pistol primers are easier to ignite. Hmmm, I’m not so sure about that. What IS a fact is that Federal primers are easier to ignite than CCI and some other brand. Many single action shooters have their hammers tuned very light. They can shoot Federals. With other primer brands the primers won’t go of.

    In general, the .45 GAP was a solution in search of a problem. I suggest sticking to the .45 ACP for revolvers. With beveled chambers and moon clips you’ll be able to load plenty fast.

  • bob

    I own an Glock 21 and 22. They are both nice shooting guns. I just bought a Glock 37. It doesn’t have the capacity of the 21 or 22 but it is has some very subtle improvements over the older models. It’s an innovative gun which would only appeal to a gun lover like me. I also ordered 200 rounds of ammo at around 50 cents a round which seemed in line with what I pay for most of the 45 ACP rounds I buy. The ammo was not hard to find, in fact there seemed to be more of it since there isn’t the demand for it that there is for 45 ACP. I plan to get a lot of use out of it and, hey, it’s a Glock, how bad can it be?