The Colt M1911 is a semi-automatic, magazine-fed, .45 caliber handgun. John Browning sold the original design to Colt, when it became the standard-issue side arm for the United States Armed Forces from 1911 to 1985, and is still carried by some US troops today, although it was largely phased out in favor of the M9. It fires the powerful .45 ACP round, which causes more tissue disruption than the 9mm Parabellum, but has more recoil and has less ammo than comparably sized 9mm handguns.