Perfect for building your custom Mk4 upper group. Comes with properly installed M4 barrel extension. All barrel sub-assemblies are properly headspaced. Made of 4140CM with a SBN Finish. - CALIBER: .350 Legend - BARREL: 16.1 1:16 twist medium taper 4140CM SBN - MUZZLE: Threaded 1/2-28 (9mm) - GAS PORT LOCATION: Carbine Length – .750 Gas Block Journal - WEIGHT: 1lb 9oz
