The Colt M16 SP1 is a usa-made semi-automatic rifle chambered in 5.56x45mm NATO, introduced in 1969. Primary use: sport, military, hunting. Type: Rifle Action: Semi-Automatic Caliber: 5.56x45mm NATO Capacity: 30 Year introduced: 1969, USA Weight: 86 oz Overall length: 39.5" Status: Discontinued Intended use: sport, military, hunting