.45 ACP

**.45 ACP** was designed by John Moses Browning for the 1911 pistol and adopted by the U.S. military in 1911, serving as the standard American service handgun cartridge until 1985. It is slow, heavy, relatively low-pressure, and beloved. In the modern era, 9mm has taken nearly every job .45 ACP used to do — including most defensive roles, most police sidearms, and most civilian carry pistols. But .45 persists: in 1911 platforms, in shooters who prefer the recoil impulse, in the subsonic niche (the cartridge is naturally subsonic, making it a natural suppressor host), and in a segment of the community that simply prefers the big, heavy bullet. It remains a perfectly viable defensive cartridge. It also remains more expensive to shoot and lower-capacity to carry than 9mm, which is why most buyers today pick 9mm first.