L.E. Wilson B-337 Hardened Steel Neck Sizing Bushing The Neck Die Bushing fits in the Neck Die andsizes the case neck to grip the bullet Bushing Size = Diameter of a loaded round -.003 (Ex. .268 - .003 = .265) Bushings are taper reamed so the top side (Number Side Up) is a bit smaller than that of the base To be used in conjunction with the L.E. Wilson Interchangeable Bushing Neck Die Made in the U.S.A