An AR-10 bolt carrier group (BCG) without hammer is a critical assembly for AR-10 rifles chambered in .308 Winchester or 7.62×51 NATO, but does not include the hammer from the fire control group. It consists of the bolt, carrier, gas key, firing pin, cam pin, and retaining pin. The AR-10 BCG without hammer works with AR-10 upper receivers, .308 barrels, charging handles, and lower receivers. It ensures reliable cycling, chambering, extraction, and firing, while the hammer is installed separately in the lower receiver.