RIFLE: BUSHMASTER FIREARMS MODEL XM15-E2S - RIFLE, SERIAL NUMBER L069473, BLACK (MATTE), CASE NOT INCLUDED, SEMI - AUTOMATIC, 5.56 NATO, 16" Notes: The Bushmaster XM15-E rifle is a family of AR-15-pattern, gas-operated, semi-automatic rifles produced by Bushmaster. The XM15 line has been offered in several configurations, including traditional 20-inch rifles and 16-inch carbine-style models, so exact specifications depend on the particular variant. Bushmaster documentation identifies the XM15-E2S as chambered for 5.56mm NATO/.223 Remington, with forged aluminum receivers and detachable magazines. Manufacturer: Bushmaster Firearms International Model family: XM15 / XM15-E2S Type: Semi-automatic rifle/carbine Platform: AR-15 pattern Caliber: 5.56x45mm NATO / .223 Remington Action: Gas-operated, rotating-bolt system Barrel options: Common configurations include 16-inch carbine and 20-inch rifle barrels. 20-inch configuration: Approximately 38.25 inches overall and 8.27 lb. unloaded according to Bushmaster's manual. Rifling: Older XM15-E2S examples are documented with a 1:9-inch right-hand twist. Receivers: Forged aluminum upper and lower receivers on traditional XM15-E2S models. Magazine: Detachable AR-15/M16-pattern magazines; 30-round magazines were standard in some configurations, subject to applicable laws. Sights: Configuration-dependent; traditional models commonly use an A2-style front sight with either a fixed or removable rear/carry-handle arrangement.