So I just got my Hornady Headspace Comparator tool in. Having some issues with 6mm arc and a possible oversized chamber. In any case I took my first set of measurements today. and had some questions. Mainly what is the acceptable variance in these measurements? Given good bullets, when using my bullet comparator, I generally get one number, say 1.156. and out of say 20 measured I might have 1 at 1.155 and one at 1.156, but the vast majority are all at 1.156. basically a small sampling at +/- 0.001.
Brass is Hornady and was factory loaded new and has just been resized for the first time. I was fortunate to have 10 unfired factory rounds left which I measured for comparison
Factory new ammunition
7 at 1.184
3 at 1.183
Once fired first resize
5 at 1.182
4 at 1.183
1 at 1.184
Out of curiosity I also measured my go/no-go gauges.
Go 1.184
No-go 1.190
Unfortunately I don't have any fireformed brass to measure, but I am hoping to next week.
But back to the main question. How much variance is normal and or acceptable when measuring sized brass from cartridge base to a point on the shoulder (headspace).
Brass is Hornady and was factory loaded new and has just been resized for the first time. I was fortunate to have 10 unfired factory rounds left which I measured for comparison
Factory new ammunition
7 at 1.184
3 at 1.183
Once fired first resize
5 at 1.182
4 at 1.183
1 at 1.184
Out of curiosity I also measured my go/no-go gauges.
Go 1.184
No-go 1.190
Unfortunately I don't have any fireformed brass to measure, but I am hoping to next week.
But back to the main question. How much variance is normal and or acceptable when measuring sized brass from cartridge base to a point on the shoulder (headspace).
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