95 AR-9 9MM 5" UNASSEMBLED PISTOL UPPER / BCG AND CHARGING HANDLE / MLOK. . 99 9MM Upper Assembly 7. 99 $ 349. The patent pending roller-delayed action of the MDP-9® significantly reduces the weight and recoil of the gun. This listing is for an R&D Precision PW-9 V1 (Gen 1) Complete Bufferless AR9 Upper Assembly, which includes a complete 9mm upper receiver (including proprietary BCG + forward/side charging handle) AND the "buffer-tube-less" recoil assembly (with 1913/picatinny rear rail).