Andro Corp Industries 5.56 NATO 16" M-LOK Upper Receiver

Sixteen inches is the rifle length answer, the barrel that keeps an AR-15 clear of short barrel rifle territory and still balances well in the hands. Andro Corp Industries chambers this one in 5.56 NATO, which also handles 223 Remington, and wraps the barrel in an M-LOK handguard for lights, hand stops and sling mounts. The upper drops onto a standard AR-15 lower receiver, so a shooter with a lower already on the bench can finish a carbine with one part.