Glock 21 Gen4

The Glock 21 is the dominant polymer-framed .45 ACP pistol, offering the same legendary reliability Glock delivers in 9mm but chambered in a round with a 115-year service record. At 13+1 capacity, it outpaces virtually every traditional .45 design on the market, including the 1911 (7+1 or 8+1) and the SIG P220 (8+1), while bringing that capacity in a pistol that field-strips without tools and runs anything from 185-grain hollow points to 230-grain ball. Law enforcement agencies that issue .45 ACP have standardized on the G21 precisely because it pairs the round's terminal performance with a platform that requires minimal maintenance and training overhead.

The Gen4 update brought three meaningful improvements: a dual recoil spring assembly that reduces felt recoil and extends spring service life, interchangeable backstraps (small, medium, large) that let the shooter dial in grip fit without aftermarket parts, and a rougher RTF (Rough Textured Frame) surface for positive grip in wet or gloved conditions. The frame also includes a reversible magazine catch for left-handed shooters. These changes addressed the most common ergonomic complaints about earlier G21 generations.

One practical advantage often overlooked is magazine compatibility. The G21 accepts G30 subcompact .45 ACP magazines, giving shooters a compact backup magazine option that still functions reliably in the full-size gun. Compared to the 1911, the G21 requires none of the finicky magazine selection, hand-fitted components, or ammunition sensitivity that characterizes traditional single-action .45s. For shooters committed to .45 ACP who want modern reliability and capacity, the G21 Gen4 is the baseline against which every other polymer .45 is measured.