Our 49/64-20 TPI threaded jam nut is perfect for your .50 Beowulf or 12.7×42 chambered rifle. Whether it is a precision bolt action rifle or AR15 platform rifle or other sporter rifle chambered in .50 Bewoulf or 12.7×42. It allows you to perfectly time your muzzle brake or compensator or suppressor without the use of a work bench or vise. Keeps the install process overall simple and only requires a thin open end wrench to tighten down. Precision machined from carbon steel and finished in black nitride. Please ensure your barrel is threaded 49/64-20 thread pitch. These jam nuts are reusable and can be transferred from one rifle to the next.