ArmaLite's barrels are custom-made for extreme accuracy and long life. This complete AR-10 SASS barrel assembly includes an adjustable gas block, barrel nut, gas tube.
.875 at the Journal (Under the gas block)
Caliber: .308/7.62 X 51mm NATO
Barrel: 20" Triple lapped, Ceramic Coated AISI 416R Stainless Steel Match, Threaded 5/8x24, M-4 Feed Ramps
Rifling Twist: RH 1:10"
Muzzle Device: Flash Suppressor