Lead and Steel AR9 Barrel Features The Lead and Steel AR9 barrel is machined from chrome moly vanadium steel and treated with a black nitride finish that improves both corrosion resistance and surface hardness. Because the AR9 platform operates on a blowback gas system this barrel requires no gas block or gas tube simplifying the parts list and assembly process for anyone building a 9mm pistol-caliber carbine upper. A 1:10 twist rate is matched to typical 9mm bullet weights for stable accurate flight. The threaded muzzle cut to a 1/2x28 pattern allows shooters to add a compensator flash hider or suppressor depending on their build s intended use. At 4.5 inches this barrel suits a compact AR9 pistol or short-barreled build where maneuverability is a priority. Compatibility with both standard mil-spec uppers and dedicated AR9-specific uppers gives builders flexibility in how they configure their platform. Weighing just 8 ounces the barrel keeps the front end of a 9mm build light which helps offset the added weight of a bolt carrier group designed for blowback operation. This barrel is a solid affordable option for anyone assembling a compact 9mm AR-pattern carbine or pistol. Lead and Steel AR9 Barrel Specifications Manufacturer: Lead and Steel Model: AR9 Caliber: 9mm Barrel Length: 4.50 Barrel Finish: Black Nitride Barrel Material: Chrome Moly Vanadium Barrel Description: Threaded Twist Rate: 1:10 Thread Pattern: 1/2x28 Weight: 8 oz Available At: GrabAGun