The two photos below are from the same batch of processed LC brass. Nothing different between the two, same time resizing, trimming and swaging.

Are the differences of these two in the headspace gauge something to be concerned with? My understanding is that the first one is okay, would like your opinion on the second one. Does it need to be sized again?

And as a caveat, these were loaded inert, just trying to get used to setting the seating and crimping dies.

Looks like You need to bump that shoulder back a tiny more so the rounds sit flush in the gauge.

Do they fit in the gun?

Or is there a little dimple or damage to the rim that can be keeping the case from sitting flush. (I know the 308 doesn’t have a rim per say)
My 45 pistol almost tears the cases out of the chamber and some won’t fit in the case gauge but do chamber in the gun.

Did they fit the case gauge before you loaded the bullets in the case?
If they don't then its most likely the rim is slightly damaged as Mike suggests. I have fixed some of those by lightly filing the edge of the rim.
I also have had to resize a number of cases more than once to get stubborn cases to fit the gauge.

I would suggest getting if you don't already a comparator like what Honady or others and measure the shoulders (and OG is helpful too).

This is my foolproof method on checking headspace and setting up my die. No guesswork at all.



Tony.