L.E. Wilson's steel neck sizer bushing is made of hardened stainless steel and is available in .001” increments for precision sizing.
The bushing features a .003” taper and can be flipped to achieve a slightly tighter sizing in emergency situations or for fine-tuning.
To select the correct bushing size, subtract .002" to .003" from the outside neck diameter of a loaded cartridge or calculate based on case neck wall thickness and bullet diameter.