Proof Research AR Barrels Features Proof Research designed this barrel around their Caliber Matched Gas System a design philosophy built on the observation that higher performance cartridges maintain higher bore pressure further down the barrel than the 223 Rem and 5.56 NATO cartridges the AR-15 platform was originally designed around. By tuning the gas port location to match the specific cartridge and barrel length Proof ensures the gas system pressure behaves the way the AR platform was originally engineered to handle. The result is a noticeably softer recoil impulse reduced fouling inside the receiver and more reliable extraction cycle after cycle. Chambered in .223 Wylde this barrel is built to handle both 223 Rem and 5.56 NATO ammunition with excellent accuracy across both chamberings. Machined from stainless steel with a 1 in 8 twist rate this 20 inch barrel is threaded 1/2x28 at the muzzle giving builders the option to add a muzzle brake compensator or suppressor without any additional gunsmithing. The threaded barrel design also protects the crown from damage during handling and transport an important consideration for a barrel this length. Reduced wear and tear on brass a direct result of the tuned gas system means handloaders get more reloading cycles out of their cases before they need replacement. For AR-15 builders seeking a drop-in barrel upgrade that reduces recoil and improves reliability without complicating their build this Proof Research barrel delivers a well-engineered solution. Proof Research AR Barrels Specifications Manufacturer: Proof Research Compatible Hosts: AR-15 Caliber: .223 Wylde Barrel Length: 20 Barrel Material: Stainless Steel Twist Rate: 1:8 Barrel Type: Threaded Muzzle Thread: 1/2x28 Color: Silver Gas System Length: Rifle Length Available At: GrabAGun