Your bolt-action barrel will arrive ready for thread and chamber by your gunsmith. When PROOF Research joined with Lawrence Barrels in 2012, they acquired 15 years of experience in manufacturing precision steel barrels. PROOF now manufactures stainless steel barrels in-house with an absolute commitment to extreme accuracy and quality. They start with double stress-relieved 416R stainless steel, a pre-hardened chromium stainless steel ideally suited for use in precision, match-grade rifle barrels. 416R was specifically designed by engineers in collaboration with barrel makers and rifle manufacturers to provide the consistency, high quality and durability the firearms industry demands. Mfg: Proof Research