Ruger Upper Carbine Receiver Assembly

Carbine receiver assembly is a standard model 5.56MM with an integral flash suppressor and fluted barrel. Overall length is 23.75 inches; barrel length is 16.12 inches with a weight of 5.29 pounds. It features a black anodized aluminum finish, folding sights, three 30 round magazines, rail covers, sight tool, soft case, manual and lock. Barrels are heavy contour (.850 inch under the hand guard), chrome lined, cold hammer forged 41V45 steel. Twist rate is 1 in 9, exterior barrel and gas block finish is Manganese Phosphate.Piston, regulator and gas block interior are chrome plated. The barrel threads are ½ inch-28 on 5.56MM. Back up iron sights are Troy Folding Battle sights. Quad rail by Troy. Barrel is not free-floated; the system is pinned together and functions like a monolithic upper. Transfer rod is not user accessible.