DANIEL DEFENSE DDM4 PDW 5.56 Nato 10.3" Barrel Pistol w/ No Brace. The Daniel Defense MK18 Pistol features the picatinny quad rail Daniel Defense currently provides to USSOCOM and a 10.3 inch Cold Hammer Forged Barrel, the same length commonly used for CQB operations. The MK18 RISII features the Bolt-Up System and has been rigorously tested prior to fielding by USSOCOM. The independently ambi GRIP-N-RIP Charging Handle accommodates left- and right-handed shooters. This pistol comes equipped with the ergonomic Daniel Defense Pistol Grip with an integral trigger guard and soft touch overmolding.