Daniel Defense AR-15 MK18 Pistol Upper Receiver Assembly 5.56x45mm 10.3" Barrel

The Daniel Defense MK18 Complete AR-15 Pistol Upper Assembly is a faithful recreation of the US Navy's Mk18 Mod 1 platform, and features a Premium 10.3" Cold Hammer Forged Barrel made from Mil-Spec 4150 Chrome-Moly Vanadium Steel that is Chrome Lined for durability and corrosion resistance. M4 feed ramps are incorporated into the barrel extension and upper to enhance reliable feeding, while a true 5.56x45 NATO chamber ensures that both commercial and higher pressure surplus mil-spec ammunition may be safely used. The bolt and carrier both pass a thorough Magnetic Particle Inspection (MPI) test for guaranteed structural integrity, and the gas key is properly staked to its mil-spec bolt carrier. All steel parts feature a heavy Mil-Spec Phosphate finish for superior corrosion resistance and durability, while aluminum parts are Type III Hard Coat Anodized. This upper comes equipped with a 9.5" Flat Dark Earth RIS II Mk18 Quad-Rail Handguard that covers a pinned, low profile gas block at the carbine gas port position and Free Floats the barrel for increased accuracy potential. The RIS II provides ample room for adding tactical accessories, while also creating a full length, uninterrupted top rail surface with the A4 Flat-Top receiver that can accommodate a shooter's chosen optic and/or iron sight arrangement. Complete with charging handle assembly and Daniel Defense Flash Hider, the MK18 upper is ready to drop onto any pistol or registered SBR small pin lower receiver.