.32 ACP

.32 Automatic Colt Pistol (7.65X17mm) - 1899 - John Browning

Diameter - .309 Inches

The .32 ACP (Automatic Colt Pistol) pistol cartridge is a semi-rimmed, straight-walled pistol cartridge developed by firearms designer John Browning. It has the added noteriety of being his first pistol cartridge design. The .32 ACP needed a straight wall for reliable blowback operation as well as a small rim for reliable feeding from a box magazine. The cartridge headspaces on the rim. The cartridge was a success and was adopted by dozens of countries and countless governmental agencies and is often found in smaller pistols designed for concealed carry.