Thread: Headspace gauge/ case head separation

A headspace gauge and a case comparator gauge are different things. I don’t mean to point out the obvious if you know this, but just checking.
The headspace gauge will check safe headspace in your rifle, which most people don’t bother with in a new rifle as it should not be out of spec. But by all means check it if you feel like it.

A case comparator gauge measures cases to compare the difference between fires/unfired, sized/unsized etc, so you can size your cases appropriately. Case comparators are strictly only for comparing one case to another, not for comparing chamber headspace to SAAMI specs.

You can reduce the amount your are sizing your cases without the need for comparators anyway. Simply wind your dies out and make a minimal sizing pass, and try the brass in the chamber. Repeat until the case will chamber, and you can feel the slightest amount of resistance on the bolt handle where the case shoulder is meeting the chamber shoulder (or whatever datum
Point the case is meeting on). Once your dies are adjusted thus, size the rest of your cases and periodically check the occasional piece in the chamber.

As an aside, I never use the terminology ‘bumping shoulders forward’ because you can’t move case shoulders forward with dies. Shoulders might move forward upon firing and May move back when sized. I describe the process as above; ‘reducing the amount of full length sizing’ as this is less confusing to beginners. But hey that’s just me.