The 25 ACP (Automatic Colt Pistol), also called 25 Auto, was designed by John Browning in 1900 to fit into a radically small semiautomatic pocket pistol of his design. Traditionally loaded with a 45-grain jacketed bullet at 815 feet per second, the 25 ACP produces just 66 foot-pounds of energy, far below many 22 Long Rifle loads. It is thus more of a deterrent than an effective personal defense cartridge, but it has the advantage of being housed in extremely small handguns for purse and pocket carry. 25 ACP pistols have been widely manufactured, and most major suppliers of handgun ammunition load for it.
