ABC RIFLE COMPANY AR-15 7.62x39mm Micro Pistol 5in Barrel M-LOK Handguard Upper Receiver w/BCG And Charging Handle Robbin's Egg Blue UA762-BR5-ML4D-RB. The 5in 4150 CMV barrel with a 1:9.5 twist is optimized for 7.62x39mm and paired with a 5/8x24...