The Colt's Manufacturing Colt M1911 1918 Production is a usa-made semi-automatic pistol chambered in .45 ACP, introduced in 1918. Primary use: military. Type: Pistol Action: Semi-Automatic Caliber: .45 ACP Capacity: 8 Year introduced: 1918, USA Weight: 30 oz Overall length: 8.5" Status: Discontinued Military use: Yes Intended use: military