10.5 inch 458 Socom AR-15 Barrel, 4150 CMV and Nitrided, 1/14 Twist, Heavy Contour Barrel Profile with Pistol length Gas System - made by Tactical Kinetics. Our Tactical Kinetics AR platform barrels are constructed from the finest domestically sourced steels, are drilled, reamed, and button rifled, and then profiled and chambered to exacting dimensions in compliance with SAAMI Specifications. Our high-precision manufacturing processes ensure both accurate and repeatable performance for thousands of rounds. Weight 2 Length 10.5 Profile Heavy Twist 1:14 Finish Nitride Material 4150 CMV Thread Pitch 5/8-24 Caliber 458 Socom Feed Ramp Single Large Flutes N/A Gas System Pistol Rifling Conventional Gas Block System 0.936 *Warning* - 5/8-24 muzzle devices for 300 Blackout or 30 cal cannot be used with this barrel. Only muzzle devices specfically made for this caliber are compatible.