The REC7 is Barrett's AR-15 pattern rifle built around a short-stroke piston system rather than the standard DI gas system. The piston operation reduces heat and carbon fouling at the bolt carrier group, extending service intervals in sustained fire. It was evaluated by US military units seeking a more reliable alternative to the M4. Type: Rifle Action: Semi-Automatic Caliber: 5.56x45mm NATO Capacity: 30 Year introduced: 2007, USA Weight: 176 oz Overall length: 36" Status: Active Military use: Yes Intended use: Military, Law Enforcement, Tactical