Our UM Series is built with Extreme Accuracy as its primary focus. The backbone of every Rainier UltraMatch Upper starts off with a barrel made from a world renown SHILEN blank and the ultra precise Rainier Billet Upper. Look at the list of components and see for yourself. This upper is the best money can buy. Guaranteed to shoot SUB-MOA with match grade ammo and should group 1⁄2 MOA. All our custom uppers come complete with a limited lifetime warranty on all parts & workmanship.
Rainier Arms 16" UltraMatch Barrel Midlength Gas System 1:8 Twist Ratchet Rifling Bead Blasted Finish Rainier Arms UltraMatch Billet M4 Upper Receiver Centurion Arms C4 Rail System 12.0 Low Profile Pinned Gas Block NIB Full Auto BCG Rainier Arms Raptor Ambidextrous Billet Charging Handle Rainier Arms XTC Compensator