Hey everyone, I think we need to get back to basics, every die company makes them a tiny bit different, then you account for an assumed amount of spring back, and factor in machining tolerances, no two die companies make them the same. That being said, I can run new starline brass through my lee dies and get .305 inner diameter, with an .011 wall thickness, then form one from a 38 spc case, and get .301 inner diameter with the same wall thickness. Stands to reason that if you are reloading fired brass you will have issues if you dont anneal the case mouths. I have had spring back problems with large rifle cases before, but this is the first time I have tested and measured the result. Hope this helps.
