Faxon Firearms Big Gunner Barrel Features The Faxon Firearms Big Gunner Barrel is machined in-house from certified 4150 CMV steel then button rifled with a 1:16 twist rate specifically tuned to stabilize the heavy large-diameter bullets used in .450 Bushmaster. The Gunner Big Bore profile balances weight and rigidity for a cartridge known for its stopping power on big game while the .875 gas block diameter and 1.1 journal length ensure compatibility with big-bore-specific gas blocks. A carbine-length gas system keeps the barrel s overall length manageable at 16 well suited to close-range hunting and defensive applications where a shorter harder-hitting rifle is an advantage. The dedicated Big Bore barrel extension ensures proper headspacing and reliable function with .450 Bushmaster-specific bolts and magazines. Every barrel is finished with Salt Bath Nitride both inside and out providing excellent corrosion resistance along with a smooth bore that eases cleaning after a hunt. The muzzle is threaded 11/16x24 to accept .450 Bushmaster-specific muzzle devices and a polished 11-degree target crown protects the rifling from damage while supporting consistent accuracy. Each barrel undergoes magnetic particle inspection and precision headspace gauging before it ships reflecting Faxon s commitment to quality control at every stage of production. For hunters and shooters who want a hard-hitting dependable .450 Bushmaster barrel for their AR-platform rifle the Big Gunner Barrel delivers proven performance. Faxon Firearms Big Gunner Barrel Specifications Brand: Faxon Firearms Model: Big Gunner Type: AR Rifle Barrel Caliber: 450 Bushmaster Barrel Length: 16 Barrel Profile: Gunner Big Bore Barrel Material: 4150 CMV Rifling: Button Rifled Twist Rate: 1:16 Finish: Salt Bath Nitride Muzzle Thread: 11/16x24 Gas System: Carbine Gas Block Diameter: .875 Barrel Extension: Big Bore Weight: 1.72 lbs Available At: GrabAGun