Photos & Story
by Larry S. Sterett
Contributing Editor

The .45 ACP cartridge is only a couple of years shy of the century mark in age. It has been a tried and true cartridge, and in the M1911 pistol, and its many variants, it has seen yeoman duty on both the civilian and military fronts.

Once the M1911 evolved from the M1905 pistol in which the .45 ACP cartridge was introduced, it became, for the most part, the only pistol so chambered. Some licensed versions were manufactured in Argentina and Norway, and in Mexico the Obregon had the appearance of a M1911, but featured a rotating barrel rather than a swinging link lock.

(There were a few prototypes of other designs in these calibers, including the Parabellum and later Walther, plus a few Chinese-manufactured M1896 Mauser versions.) It was not, however, until after World War II that other pistol designs in this caliber began to appear, along with many copies of the original Browning design.

During the same period the cartridge remained much the same, with 230-grain ball and 185-grain semi-wadcutter loads being the main choices for ammunition. Then came new loads with higher velocities, hollowpoint and softpoint bullets, short range loads, such as the Glaser, and even some "wildcats."

The .45 ACP cartridge has a loaded length of 1.24 inches and a case length of 0.898-inch. These dimensions are pretty much determined by what can feed reliably through the box magazine and be ejected through the slide port. The ejection port can be opened slightly and contoured to handle a slightly longer case, but it still has to feed through the magazine.

As a result, attempts to lengthen the cartridge slightly and modify the M1911, etc., pistol to handle such rounds have been rather limited. Two such souped-up cartridges include the .45 J-Mag and the .45 Super. More of a trend, if it can be called such, has been to neck the .45 ACP case down to a smaller caliber, resulting in the .38/45 Clerke, .41 Avenger, and .400 Cor-Bon.

This last cartridge, the .400 Cor-Bon, is the only one to reach commercial production on any measurable scale and several pistols and/or drop-in barrels are available. It's possible someone may have produced a "wildcat" .375/.45 or 9.5mm ACP, but this shooter is not aware of such a cartridge.

The .45 ACP is a great cartridge, and easy to handle in the M1911, but some shooters have complained the cartridge produces too much recoil. These same shooters would no doubt have complained the 10mm (Bren) produced too much recoil. As a result the excellent 10mm is not often heard about, nor are as many pistols available for it as there are for the shorter .40 Smith & Wesson cartridge.

Now, after nearly a century, the .45 ACP has been shortened, and we have another new .45 pistol cartridge, the .45 GAP, or as it was first tabbed, the .45 Glock. Its case, which headspaces on the mouth, is short enough so that a pistol chambered for it will not accept regular .45 ACP cartridges. Nor will the magazine of the new Glock Model 37 pistol accept regular .45 ACP cartridges.

The new Glock pistol measures 8-1/32 inches long with a barrel length of 4° inches, weighs 28 ounces empty, stands 5° inches high and has a maximum width of 1-1/8 inches. Capacity of the steel-lined synthetic magazine is 10 rounds, and it does require the slip-over loader for loading to capacity.

The dimensions of the new Model 37 help explain the reason for the new Glock Automatic Pistol (GAP) cartridge. The Austrian firm already makes .45 ACP models-the Models 21 and 30, but the dimensions of the ACP cartridge make it impossible to design and make a pistol as slim as the original Model 17. Creation of the shorter .45 GAP made it possible to manufacture a .45-caliber automatic pistol as slim as the Model 17; and the new cartridge was designed to provide ballistics comparable to the century-old .45 ACP.

The new Model 37 resembles most Glocks, except the slide stop release is a bit handier to use than the early flat designs. The caliber-.45 GAP-is indicated in four locations on the Model 37: on top of the barrel chamber, on the back of the magazine, on top of the magazine follower, and on the left side of the slide. There's no reason to attempt to load the wrong ammunition in this pistol, provided the shooter can read and is observant.

Besides the serial number on the barrel, underside of the frame and on the slide, markings on the Model 37 include the Glock logo on both sides of the slide, and left grip, barrel back of magazine body and on the floorplate. The country of origin is indicated on the left side of the slide, right side of the frame and back of the magazine body. The model number (37) is on the left side of the slide, with the US patent numbers and Glock's US address on the right side of the frame.

Sights on the Model 37 include a 0.162-inch wide front post with 0.100-inch white dot on the face, and a drift adjustable rear featuring a white outlined 0.137-inch square notch. Sight radius measured 6° inches.

The Glock 37 is Glock all the way, from the Polymer 2 receiver with chrome steel frame rails, Tenifer-treated carbon-steel slide and hammer-forged barrel, and "Safe-Action" trigger to take-down or disassemble. This "Safe-Action" trigger is one of the many unique features of the Glock design.

Projecting from the lower center of the trigger is a thin lever or small sub-trigger which will bear against the frame preventing further trigger movement unless it is actually depressed by the trigger finger. This is the first safety, and could be thought of as being similar to the grip safety on the Browning designed M1911. Additional rearward movement (approximately 1/4-inch) of the trigger will disengage the second or striker safety permitting the striker (firing pin) access to the cartridge primer.

Continued rearward movement of the trigger will shortly reach the "trip" point, disengaging the third safety, sort of like releasing the catch on a tightly wound catapult, and the compressed striker spring will drive the striker forward into the primer. Total trigger movement is about 7/16-inch or just under 1/2-inch. Due to the rather long take up, the let-off may seem heavy, but on the test gun it measured 5-1/2 pounds, which is fine for a carry gun.

Available Loads
Currently there are four loads available for the .45 GAP, all from Alliant, three from Speer and one from Federal. These include the 200-grain TMJ round from Speer, 200-grain JHP and 185 JHP Gold Dot rounds also from Speer, and the 185-grain Hydra-Shok from Federal. All four were fired into saturated wetpack at 10 yards to determine how they performed in the expansion and penetration department. The results were excellent.

The Speer 200-grain TMJ solid passed through 8 inches of saturated wetpack and another 6-3/8 inches of compressed wet phone directories, leaving a wound channel you could easily stick a finger into. The 200-grain Gold Dot hollowpoint penetrated 7° inches, and expanded perfectly to over .72 caliber, while the 185-grain Gold Dot expanded to .77 caliber and penetrated 6-5/16 inches.

Federal's 185-grain Hydra-Shok expanded to .73 caliber and penetrated 5 inches into the saturated wetpack. The Speer TMJ round is good when penetration is needed, but the three hollowpoint rounds expand rapidly and dump their energy within the body of the target. (The recovered bullets showed weight losses of less than 2%, with the TMJ bullet showing no noted weight loss or deformity, only rifling marks.)

To check the new Glock for functioning and accuracy it was taken to the range along with a supply of each of the loads currently available. Firing was done from the bench at 25 yards, using a two-hand hold, wrists resting on a sandbag. The targets used were NRA 50-yard Slow Fire/25-yard Rapid Fire versions having black bulls (nine and 10 rings) measuring 5-9/16 inches in diameter.

Flawless Feed
Cartridges fed flawlessly from the magazine, and fired cases were ejected to the right and one to two paces to the rear. The slide locked open when the magazine was empty, and the magazine dropped free when released. With the Glocks' wide magazine well, insertion of a loaded magazine was a breeze, and pressing down on the slide release permitted the slide to move forward chambering a fresh cartridge.

Three-shot groups were fired, and the smallest one, fired with the Speer Lawman 200-grain TMJ rounds, measured 1-3/16 inches in diameter, center-to-center, all in the 9 ring using a 6 o'clock hold. Without drifting the rear sight, all the groups tended to be slightly high and to the left of the point-of-aim, with the majority being in the black.

Speer's 185-grain Gold Dot hollowpoint load and Federal's Premium 185-grain Hydra-Shok rounds both produced groups measuring just over 2 inches, and in the 9 and 10 rings. Speer's 200-grain Gold Dot hollowpoint load produced some groups in the black, with shots from a couple of groups landing in the 8 ring, probably due to a pull on this shooter's part.

The new Glock Model 37 and the cartridges currently available for it make a great combination for shooters wanting a .45 with plenty of knockdown ability and slightly less recoil than the regular .45s. Recoil of the .45 GAP in the Model 37 is relatively mild and muzzle rise was not much more than with some 9mm Parabellum pistols, and possibly even less.

Recoil, however, depends on pistol weight, action type, grip shape, and is subjective. What one shooter considers mild, another might not. Still, overall, the new Glock and the .45 GAP cartridges should win lots of new friends.