After numerous customer requests to design a drop-in barrel for the Remington Model 700, Shilen has done that and more by designing their patent pending dual threaded Alternut System that will bring the ease and flexibility of drop-in barrels to even more platforms. The dual thread system was designed to increase the barrel diameter and wall thickness at the chamber end while still using a lock nut. To make things even easier for customers, these many configurations use a Large Shank Savage lock nut. Alternut barrels come threaded and fully chambered to be installed into the action with no additional machining or modification needed. Shilen recommends that actual headspace gauges be used to determine if a barrel is properly installed and head spaced.