I just purchased a nice old Mauser '98 in 7x64. I fired a dozen cartridges this afternoon. I measured the headspace, using the Hornady headspace tool and my digital calipers to compare the difference between fired and factory new cases. From base to datum line on the shoulder, the cases have expanded is 0.012". The measurement is the same for PPU, RWS, and Speer cases / ammunition. Is this too much? My understanding is that a difference of 0.010" is about maximum. Your thoughts?
