Introduced in 2000, this rifle is chambered for the 50 BMG cartridge. The upper left side of the receiver is marked with the Armalite logo followed by "AR-50A1" and the serial number and is fitted with a Picatinny rail. The left side of the barrel is marked ".50 BMG" and it is equipped with the proprietary Armalite designed muzzlebrake. Single stage trigger, checkered plastic pistol grip and mounted with a three piece hard anodized aluminum stock and extended forearm and adjustable Pachmayr Decelerator recoil pad. Approximate weight is 33 lbs.