Recently I started reloading for my M1903 Mannlicher Schoenauer and while I can easily get to +/- .0005" concentricity on the case neck/body, the bullet cty is a very different matter and is inconsistent varying between .0025 & .005".

Nothing I do seems to improve matters. This is with the Hornady 160gn RN Interlock bullet.
I haven't yet tested other bullets as supplies of 159/160gn bullets in UK are pretty sparse.

Modern collar or collet dies for this cal/cartridge aren't available, so I use both Redding & RCBS dies.
Any practical suggestions?
I've tried using an expander die to aid matters, but no difference I can see.
Cheers, d