The AR-15A2 HBAR (Heavy Barrel Automatic Rifle) was the law enforcement and civilian version of the M16A2 improvements, with a heavy barrel for sustained fire. Issued to various law enforcement agencies as a patrol rifle before the AR-15 patrol rifle became common. Type: Semi-Auto Rifle Action: Gas-Operated Caliber: 5.56x45mm Capacity: 30 Year introduced: 1986, USA Weight: 8 oz Overall length: 39.5" Status: Discontinued Intended use: Law Enforcement, Patrol Rifle