Today's police handgun market abounds with full-sized, medium-sized, and compact .45 ACP pistols. But until recently the designers of these weapons all labored under a seemingly insurmountable constraint: size.
When you build a pistol for a cartridge whose bullet approaches one-half inch in diameter and whose overall length can be as much as 1.275 inches from nose to primer, even the most sub-compact pistol in .45 ACP is going to be cursed with a generously dimensioned grip.
Grip size is not an issue for officers with large hands. But if you have small hands, grip size can be a critical concern when selecting a duty, off-duty, or backup pistol. This is why officers with smaller hands have generally favored 9mm and .40 S&W caliber pistols. Still, some of these officers wanted .45 ACP pistols for more punch and sacrificed capacity to get it.
A New Cartridge
For quite some time, Glock has offered several pistols chambered for the .45 ACP round. Then a couple of years ago when the company queried its customers as to the type of pistol they would like to see next manufactured by Glock, the consensus was "...a .45 the size of the G17/22."
The firearms designers at Glock scratched their heads. Then they went to work. The solution to this conundrum turned out to be quite simple: if the .45 ACP won't fit the pistol, make a .45 caliber cartridge that will.
Glock did just that. In 2003, in cooperation with Speer, Glock introduced a proprietary cartridge that would fit into a G17/22 sized pistol, the .45 Glock Auto Pistol (G.A.P.). The .45 G.A.P.'s case measures 0.775 inches in length, but its overall length is 1.070 inches, slightly shorter than the 9mm Parabellum.
It is loaded to the same maximum average pressures as the .45 ACP +P (23,000 psi), which is less than that of the 9mm Parabellum and .40 S&W (35,000 psi). This allows the .45 G.A.P. to fit a wide range of compact and sub-compact sized pistols. For officers who desire a pistol with the performance of the .45 ACP, but who have smaller hands, the .45 G.A.P. is a wish come true.
Glock's first .45 G.A.P. pistol, the G37, features a grip frame the same size as the G17/22 pistols. But so as to accommodate the larger cartridge, the width, height and mass of the slide were increased slightly. It's been a big success.
That's why Glock recently released two new models in the .45 G.A.P. line, the compact G38 and sub-compact G39. Except for their larger slides, these guns approximate the dimensions of the G19/22/32 and G26/25/33 pistols, and were designed specifically for concealed carry by plainclothes and off-duty police officers.
I have often been criticized for saying, "A Glock, is a Glock, is a ..." Well you get my drift. But this should in no way be construed as a slam against Glock. One of the Glock's biggest advantages as a service pistol is that, regardless of which model you choose, the operating drill, method of field stripping, location of controls, etc., are exactly the same. An officer can pick up any Glock pistol in any caliber and operate it as easily as any other Glock.
There's another reason that Glock pistols are so popular with police agencies: Glock offers each officer a pistol for each need that he or she may have. On patrol or in day-to-day operations, the officer can carry a full-size duty weapon. Off-duty, undercover, or as a backup weapon, the officer can carry a compact or sub-compact that is a scaled-down version of his or her duty weapon, that works the exact same way, and that accepts the same magazines.
This makes it very easy for an officer to transition from his or her duty gun to a backup or concealed pistol. It's a great advantage of the Glock line. Hence, the .45 G.A.P. line now includes the full-size G37, the compact G38, and the sub-compact G39.