Nearly two decades of building the finest custom tactical AR-15 rifles have given us the insight to develop a comprehensive line of stainless steel, match grade barrels that offer superior accuracy, reliability and longevity for your next custom AR rifle project. All Wilson Combat Match Grade AR-15 barrels are precisely crafted of the finest American-made 416R rifle rated steel on computer controlled equipment to our exacting list of technical specifications. These proven barrels feature a hand-polished bore and feedramps and then complete a rigorous final inspection process that ensures your new barrel will meet your most demanding expectations. All barrels feature crisp CNC markings, precision muzzle crown and a chamber and gas port optimized for reliability. .300 AAC BlackoutThe .300 Blackout (.300 BLK) was designed by Remington/AAC to create a reliable, compact .30 caliber round for the AR platform that uses a standard bolt and magazine. .300 Blackout is optimized for suppressed fire with heavy bullet subsonic loads but can also be used with supersonic ammunition when extra range is needed. The 1-8î twist will work well for subsonic and supersonic loadings alike and there is typically no need for an adjustable gas block when switching back and forth between the two loadings.SPECIFICATIONSChamber .300 AAC Blackout Feed Ramps M4 Style Finish Matte Bead-Blasted Stainless Gas Block Seat .750″ Diameter by .920″ Length – Dimpled for Set Screw Gas System Carbine Length Length 16″ Material Stainless Steel, Type 416R, Barrel Grade Muzzle Threads 5/8″ x 24 Profile Tactical Lightweight Rifling 1:8, RH, Six Groove, Precision Button Rifling Weight 29 oz.