14 cases @ 1.630

27 cases @ 1.631

17 cases @ 1.632

2 cases @ 1.633

3 cases @ 1.634

2 cases @ 1.635

1 case @ 1.636

1 case @ 1.638

That's a .008 headspace variance on cases fired and extracted from the same rifle. Can anyone offer any explanation on why such a widespread variance...is this normal ? I do see that most cases (86%) fall pretty close (1.630 - 1.632)...any thoughts ? Lastly if I were to bump shoulders back by typical .002 then I'd have cases that would span 1.628 - 1.636 that doesn't seem to make sense given the chamber is a fixed measurement and I would think that one would want all cases to have same headspacing...so am I supposed to just come up with some average headspace number and hope for the best ? Any input would be greatly appreciated, thanks