After reading on here about different depth bolts & issues some folks have had with head spacing, I ordered a set of 6.5 Grendel head space gauges from Brownells. What I forgot was that I bought a set from PTG two years ago. So now I have two sets of gauges. I removed the ejector plunger from my bolt & first dropped in the PTG no-go gauge. The bolt didn't close. Great! Next I dropped in the PTG go gauge. Not so great! The bolt wouldn't close on it either. I'm scratching my head, a bit puzzled. Do I have a short chamber on this high dollar Wilson Combat barrel? I hope not!
So... I repeated the process with the Brownell (Manson) gauges. The no-go didn't go as I suspected, but to my relief, the bolt did close on the go gauge. Dummy rounds made from new, unfired brass fed & ejected without any problems manually cycling the BCG. Next, I went to the range & shot a few rounds. Checking my fired brass they were only .002" longer than unfired rounds. That told me that my chamber is good.
I repeated all the above with an Odin Grendel barrel & got the same results. The bolt closed on the Manson go gauge but not the PTG.
Here's what's a bit strange: Measuring the gauges with my Hornady comparator (B350 unit) shows the PTG go gauge is a hair shorter than the Manson. At the .35" datum line, the PTG is 1.2145" & The Manson is 1.215". So why don't my bolts close with the PTG go gauge? What's wrong with the PTG gauge?
So... I repeated the process with the Brownell (Manson) gauges. The no-go didn't go as I suspected, but to my relief, the bolt did close on the go gauge. Dummy rounds made from new, unfired brass fed & ejected without any problems manually cycling the BCG. Next, I went to the range & shot a few rounds. Checking my fired brass they were only .002" longer than unfired rounds. That told me that my chamber is good.
I repeated all the above with an Odin Grendel barrel & got the same results. The bolt closed on the Manson go gauge but not the PTG.
Here's what's a bit strange: Measuring the gauges with my Hornady comparator (B350 unit) shows the PTG go gauge is a hair shorter than the Manson. At the .35" datum line, the PTG is 1.2145" & The Manson is 1.215". So why don't my bolts close with the PTG go gauge? What's wrong with the PTG gauge?
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