I head spaced my 250 Savage with the Go gauge and when checked with the No Go the bolt still closed… with some resistance but not a lot.

I rechecked to see that the barrel was screwed in and snug to the Go gauge and fired some test loads to measure the brass. Un-fired cases measure 1.556" and Fired cases measure 1.563" for an overall length growth of .007". I believe that the cases are stretching too much, and the growth should be limited to .002' or .003"

So I measured my PTG gauges with my Stoney Point headspace gauge.

The PTG Go Gauge measures 1.561 and the PTG No-Go Gauge measures 1.561. One of them has to be wrong. I'm guessing that it is the Go Gauge that is wrong due to the amount of stretch when case is fired.

I looked up the SAAMI Specs online and they call for 1.572" +.0005" to the Datum line and .347" diameter at that point. I'm not getting that at all.

I've measured gauges and brass with the Stoney Point headspace gauge, No. B .350". The difference between the .347" and .350" may result in the differences in the measurements to the datum line.

So, I took an unfired case and added a piece of tape to the base (adding .002"), and I'm thinking of using that as the Go Gauge, and check the No Go length with the No Go gauge. Then re-check the stretch of the brass.

Am I on the right track?