The AR-10A4 carbine complete upper assembly features a double lapped, chrome lined barrel. The MIL-STD 1913 rail on the upper receiver and low profile gas block allow rapid and repeatable interchange of removable iron or scope sights. This carbine upper takes it a step further with free-float quadrail handguard specially fitted to Armalite’s low profile gas block. This allows maximum hand placement choice and accessory locations when a longer handguard is placed on a shorter gas system upper half.
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 quad-rail complete upper half assebmly
Caliber: 7.62X51 mm / .308
Barrel: 16" double lapped, chrome Lined / chrome Moly
Rifling Twist: 1:11.25" RH
Muzzle Device: Flash suppressor
Front Sight Base: Quad MIL-STD 1913 rail
Upper Receiver: Forged flat-top receiver with MIL-STD 1913 rail and forward assist 7075-T6 aluminum
Finish: Anodized aluminumum upper receiver, manganese phosphated steel barrel