Proof Research Carbon Fiber PXT Barrel Blank Features The Proof Research Carbon Fiber PXT Barrel Blank is engineered around PXT or PROOF Exponential Twist a complete rethinking of conventional rifling geometry and twist progression. By dramatically reducing rifling lead angle and smoothing projectile engagement into the bore PXT technology lowers engraving force minimizes throat erosion and creates less felt torque during firing. In controlled testing PXT barrels have demonstrated 30 to 100 percent increases in barrel life while maintaining the accuracy standards Proof Research barrels are known for. The 1:8 twist rate suits a range of .224 caliber bullet weights giving custom builders flexibility in load development. Built around Proof Research s proven carbon fiber construction this Sendero contour blank offers an exceptional stiffness-to-weight ratio reducing overall rifle weight without sacrificing accuracy or durability. At 2.5 breech diameter and a 1.2 shank diameter the blank is designed to work with common action footprints used by custom rifle builders. Weighing just 2 lbs 8 oz it is markedly lighter than a comparable steel barrel making it a strong choice for lightweight hunting rifles and precision long-range systems alike. For gunsmiths and builders seeking a premium carbon fiber foundation for their next project this PXT barrel blank is available for sale at GrabAGun. Proof Research Carbon Fiber PXT Barrel Blank Specifications Manufacturer: Proof Research Caliber: 224 Cal Action: Bolt Barrel Material: Carbon Fiber Twist Rate: 1:8 Type: Blank Grooves: 5 Barrel Description: Sendero Barrel Length: 16.5 Breech Diameter: 2.5 Shank Diameter: 1.2 Finish: Stainless Weight: 2 lbs 8 oz Available At: GrabAGun