Need a measurement on 308 Go Gauge

[DarnYankeeUSMC]

Using a headspace gauge what is the measurement to the datum point ?

 

[memilanuk]

The official measurement per the prints is 1.630".

What you (or any given individual) measure with a comparator insert may or may not jive with that, as they (the comparators) are intended for a relative measurement, not absolute. Case in point: my Forster GO gauge is marked 1.630", but with my Stoney Point insert (which as a radiused edge to the hole) it measures closer to 1.624-1.625".

 

[DarnYankeeUSMC]

I apreciate the info. I was comparing what my full lenght sized brass is. I new that the datum point was supposed to be the 1.630. My full sized is way under that and was concerned about light primer hits on a newly installed barrel. I use a Hornady gauge to measure with and do not have a go gauge. New brass out of the bag measured smaller than the sized.