I just dont get what value there is in doing this. If I zero my caliper with the hornady comparator in it. Then measure my fired brass. Its a hard number. I size my brass .002 shorter. It doesnt matter if the comparator is on the true datum line like the go gauge.You did it fine. You don't need to have gauges. I have gauges because I spin barrels on and off when I change calibers.
Go gauge is the Saami minimum, bolt should close on it.
No go is not the Saami max though. The max is longer than no go. But if your bolt closes on a no go it would be an indicator to have it looked over.
The value of zeroing your caliper out on a go gauge is it gives you a hard known value. In win 308, that's 1.630. So if my brass grows .003 , I know it's 1.633. It's a hard actual value.
Quiet Texan conveyed what I was trying to get to. Thanks Tex!