Proof Research AR Barrel Features The Proof Research AR Barrel is chambered in .223 Wylde a hybrid chamber design that allows reliable feeding and accuracy with both 5.56 NATO and .223 Remington ammunition. Built from stainless steel the barrel offers excellent accuracy potential and a smoother bore finish compared to standard chrome-moly construction. A 1:7 twist rate stabilizes a wide range of bullet weights giving builders flexibility in ammunition selection for different shooting applications. The standard barrel profile at .750 diameter balances weight and rigidity for consistent performance shot after shot. At 11.5 long this carbine length barrel is well suited for compact AR-15 builds intended for close to mid-range use including home defense and competition carbine classes. The 5 groove rifling pattern is a proven configuration for stability and accuracy across a wide range of bullet designs. A 5/8x24 thread pattern at the muzzle accepts standard compensators flash hiders and suppressor mounts without requiring a non-standard adapter. The Proof Research AR Barrel is a precision-built component for sale at GrabAGun for AR-15 builders who demand accuracy from a compact carbine platform. Proof Research AR Barrel Specifications Manufacturer: Proof Research Caliber: .223 Wylde Compatible Hosts: AR-15 Barrel Material: Stainless Steel Barrel Type: Carbine Length Twist Rate: 1:7 Diameter: .750 Grooves: 5 Thread Pattern: 5/8x24 Barrel Description: Standard Barrel Length: 11.5 Available At: GrabAGun