RCBS Tungsten Coated Neck Sizing Bushings provide precise bullet tension without needing traditional case lube thanks to their WS2 coating.
They are self-centering and should only be used with RCBS Gold Medal Match neck sizing dies for consistent-shooting ammunition.
To select the right bushing size, subtract .002"-.003" from the outside neck diameter of a loaded cartridge or add twice the neck wall thickness to the bullet diameter and then subtract .002"-.003".