The Sig 556 features the same high performance two position adjustable gas piston operating rod system engineered by Sigs sister company Swiss Arms and marries it to a trigger housing that not only cuts the rifles weight by a pound but is designed to accept standard AR magazines. The Picatinny rail equipped receiver is made of high strength carbon steel with a durable wear resistant Nitron X rifle finish. The rifle comes equipped with a smooth two stage trigger. A 30 round magazine is supplied with each rifle.
