By offering bolt-action barrel blanks, we give you the freedom to chamber your rifle in any caliber and fit it to a wide range of actions. Our barrels come in a selection of calibers, lengths, contours and twist rates. Once you receive your barrel, it will be ready for your gunsmith to thread and chamber. This is especially useful for wildcat cartridges that have unique specifications. PROOF RESEARCH barrels are designed for safe operation within SAAMI and CIP pressure limits, ensuring reliability with most cartridges. For any questions about your rifle's performance or safety, don't hesitate to contact our customer service team. Up to 64% lighter compared to traditional steel barrels with a similar contour Enhanced thermal resistance - optimized heat dissipation for cooler and more durable barrels The product exhibits exceptional durability, being encased in high-strength, aerospace-grade carbon fiber that is infused with a proprietary matrix resin Twist rate - 1:7 Shank diameter - 1.20 inches Breech length - 2.5 inches