StormLake's Smith & Wesson barrels are machined from certified 416R stainless steel for superior strength, durability and accuracy. Barrels are match grade, hardened to 40-42 HRC, and cut broach rifled to shoot jacketed or lead bullets. All barrels are chambered for full case support. All Smith & Wesson M&P barrels are drop in and will only occasionally require modification to fit.