Because it’s not a 308 die ... it’s a NATO cartridge. thicker brass towards the inside of the case... Now you know
They’re identical cases. Even if they where slightly different which they’re not, after firing in a .308 chamber it’s now fire formed to that chamber. Thickness has nothing to do with it. It bent the expander ball shaft because the primers are military crimped.
This is the same brass I use for my prs rig and I get consistent .25-.3 moa with it. Plenty of reloads if you prep the brass properly too!! I might just have to buy another box to keep for fresh brass!!
Interesting, I thought we could onlu become sub MOA with better brass...