Why Faxon Pistol Barrels? 4150 or 416-R Stainless - Only the best steels for durability, longevity, and accuracy. 9mm SAAMI Chambers - Superior accuracy with complete SAAMI compatibility & boring reliability. Tighter Tolerances - Drop-in, yet better fitment and lock-up. Conventional Rifling - Fully compatible with cast bullets 11 Degree Target Crown Technical Specifications: Handgun Type: Sig P320 Full Size Barrel Caliber: 9mm Barrel Profile: Flame Fluted, Drop In Barrel Material: 416-R Stainless Steel Barrel Twist: 1:10 Muzzle Thread: N/A Crown: 11-degree Target Crown Rifling Method: Button Rifling Type: Conventional Inside Finish: Salt Bath Nitride Outside Finish: Salt Bath Nitride & TiN (Gold) PVD Not compatible with M17