The 45 GAP is a shorter 45 ACP due to using a smaller magazine in the Glock.You are limited to a bullet weight max of 200 grains. Can not use the 230 grain bullet in this round. The 185 to 200 grain bullets have a muzzle velocity that is comparable to the 45 ACP with the same bullets. The Federal 185 grain hydra-shock has a MV of 1,054 fps, and the 200 grain speer Gold Dot was clocked at 1,003 fps. Average group size was around 3-1/2 inches at 25 yards for all loads tested.
The slide is beefed up in weight to compersate for the increase slide speed and the shorter cartidge allows for a more compact pistol grip area that will fit most hands. For the guys who like the 45 round, but did not like the large grip on the model G21, the model G37 may be the way to go. With the 185 gr. and 200 gr. loads, it should be a good defensive pistol. The recoil is more then the 9mm, somewhat between the 40 S&W and 45 ACP.
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