Colt's modular large-frame AR-308 designed to accept an AR-15 upper, allowing users to run 5.56 and 7.62 on a single lower receiver. Type: Rifle Action: Semi-automatic Caliber: 7.62x51mm Capacity: 20 Year introduced: 2011, USA Weight: 132 oz Overall length: 35.5" Status: Discontinued Intended use: Patrol/Tactical