Rock River Arms

Rock River Arms complete Tactical Carbine upper is an A4 upper chambered in .458 SOCOM with a 16" chrome moly bull barrel and 1:14 twist. Additionally the upper comes with a complete bolt carrier group, charging handle assembly, 15" RRA lightweight M-Lok compatible free float rail and a RRA Operator brake with a 5/8-32 thread pitch. Features : - .458 SOCOM Chamber - 16-Inch Chrome Moly Bull Barrel, 1:14 Twist - RRA Operator Brake / 5/8–32 Thread - Low Profile Gas Block - RRA Lightweight Free Float Rail, 15 Inch Extended - Bolt Carrier Group And Charging Handle Assembly