With more than twenty versions of the classic Glock pistol, one of the more exotic of subspecies is the rarely seen, but often thought about .45GAP. Let's talk about this beauty of the nether regions. They really do exist. Why the need? The preeminent handgun round of the past 100-years is arguably the .45 Auto Colt Pistol (or ACP.) From the classic Colt 1911 to the space-age polymer Glock 21, the .45ACP is the benchmark that other cartridges are compared against. However, it is well known that to tame this beast, a large framed pistol with a beefy slide is needed to control muzzle flip and recoil. This puts the .45ACP out of the reach of many of the people who would most need it-- small statured men and women and older shooters. Gaston Glock started working on a smaller, but no less effective 45-caliber round to fix this-- the .45GAP The Design of the .45GAP View attachment 148916 L to R, 45GAP, 45ACP. Named the Glock Auto Pistol Round, or .GAP, this .45-caliber cartridge is shorter than your average .45ACP round. In fact, it is about as long as a 9x19mm Luger/Parabellum, but is much wider. Designed by Ernest Durham, an engineer with CCI/Speer, for Glock, the tubby round still carried a 185-230-grain bullet on its case. Ballistically speaking, .45GAP travel about 200fps faster than a standard 45ACP round, and deliver 450-550 ft/lbs of energy on target, which in many cases outclasses the ACP. View attachment 148917 In short, it has the stopping power of the average .45 cal. round, but the recoil of a 9mm. This allows big bore pistol shooters to come in more bite-sized packages as smaller framed (and gripped) firearms can be designed around the .45GAP round. Guns chambered for it To capitalize on the design, Glock introduced the new Glock 37/38/39 series pistols. The Glock 37 was a full-size combat pistol at 26/35 ounces (unloaded/loaded) and 7.3- inches overall with a 4.4-inch barrel and 10-round magazine. The pistol came out in 2003 and was a fast hit with several state police/highway patrol forces including those is New York, Pennsylvania, Georgia (Glock is made in Georgia), South Carolina, and Florida. The first 7,000 units suffered from excessively fast slides and had to be corrected before they were seen as successful. All of these in production were 3rd Generation G37s, with a small batch of 3,000 Gen4s being made just for the FHP in 2010. Now Gen4, in regular production since 2011, is the standard . A "Covert" modification, that shortens the gun to the size of a 1911 officer's size, is also popular. For those wanting a more compact version the Glock 38 as a compact version at 24/32 ounces and 6.85-inches overall with a 4-inch barrel and 8-round magazine. An even more concealable version, the Glock 39 is a subcompact at 19/25 ounces and 6.30-inches overall with a 3.4-inch barrel and 6-round magazine. Other gun makers started to look into producing .45GAP pistols including Para-Ordanance, Springfield, Ruger, and Smith and Wesson, although only the first two went past the preliminary steps. Word is even those two have shelved their production The good news is, if you are a Glock lover and want a .45ACP round without the size of a .45ACP pistol, you can pick up a 45GAP. As with most Glock models, new examples are $500-ish while used versions run $300-ish. Enjoy.