The.223 Remington cartridge (also known as the .223 Remington by the SAAMI and the .223 Rem by the CIP) is a rimless, bottlenecked rifle cartridge. It was created in 1957 by Remington Arms and Fairchild Industries for the United States Army’s U.S. Continental Army Command as part of a project to create a small-caliber, high-velocity firearm. The cartridge is known as “Cartridge, 5.56 mm ball M193” in the United States Army.