The Robinson Armament Co. XCR is a multi-caliber, gas piston weapon system developed by Robinson Armament Co. for U.S. Special Operations Command (SOCOM) to satisfy the requirements of the SOF Combat Assault Rifle, or SCAR competition, but was disqualified on a technicality due to late delivery of blank firing adapters. Robinson Armament continued development and the XCR is now being offered to law enforcement, the military and general public.