The AR-10A4 carbine complete upper assembly features a double lapped, chrome lined barrel. The MIL-STD 1913 rail on the upper receiver and the gas block allow rapid and repeatable interchange of removable iron or scope sights.
Each Armalite complete upper assembly includes a forged upper receiver assembly, barrel assembly, bolt carrier group and charging handle assembly. All complete upper assemblies are test fired as complete rifles before shipping.
.750 at the journal (under the gas block)
Model: AR-10® carbine complete upper half
Caliber: 7.62X51 mm / .308
Barrel: 16" double lapped, chrome lined, 4140 steel, M-4 feed ramps
Rifling Twist: 1:11.25" RH
Muzzle Device: Flash suppressor, threading: 5/8"-24
Front Sight Base: MIL-STD 1913 rail gas block
Upper Receiver: Forged flat-top with MIL-STD 1913 rail 7075-T6 aluminum
Finish: Hard anodized aluminum, manganese phosphated steel