Most commonly used in revolvers, the .38 S&W Special, or just .38 Special is a centerfire, rimmed cartridge designed by Smith & Wesson. Being the standard service cartridge for most police officers from the 1920s to the 1990s, including seeing use in World War I. Also designated as 9x29.5mmR or 9.1x29mmR, the .38 Special is known for its accuracy and controllable recoil. Remaining one of the most popular rounds in the world, it’s used today for both recreational and formal target shooting, personal defense and small game hunting.