The Bushmaster M4A3 Patrolman's Carbine is a law-enforcement carbine built to M4A3 configuration specifications with a 16-inch barrel, flat-top upper, six-position collapsible stock, and quad-rail handguard. Features Bushmaster's chrome-lined barrel and standard carbine gas system. Competed aggressively against Colt LE-series rifles in the patrol rifle market segment of the mid-2000s. Type: Rifle Action: Semi-Automatic Caliber: 5.56 NATO Capacity: 30 Year introduced: 2004, USA Weight: 7.2 oz Overall length: 32" Status: Discontinued Intended use: Law Enforcement, Tactical