Whether you're building a custom rifle or replacing an old barrel, your gun will benefit from a new, durable AR15 barrel. Radical Firearms manufactures rifle barrels from ER Shaw 4150 hardened chrome moly vanadium steel blanks. They send all their barrels to the best QPQ plating company in the country who handles the likes of Remington and Mossberg. They are button rifled with a 1/7 twist rate. This barrel is meant for 55 grain and heavier rounds, and will excel with 72+ grain rounds. When you're looking for a quality barrel that will provide you with accuracy and durability for your AR15, this is the one.