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hal9000
03-17-2024, 02:24 AM
I have time to figure this out since my new barrel is at least a few weeks out at the moment. But I also haven't ordered my headspace gauges yet so I can't answer the first question by just measuring.... I'm curious what the difference in length between the go and no go gauge is (if it varies, I'm going interested in 6.5 PRC) and what the tolerance range for "correct" headspace is? Also curious where in the range (ie, min, max, or somewhere in between) the go gauge would likely set headspace (I'm sure personal techniques affect this so maybe it's a dumb question)? For that matter from a practical standpoint, if I'm chasing n'ths is there any advantage to nit picking the headspace down to the last thousandth, or is good enough just fine?

Thanks everyone!

NF1E
03-17-2024, 05:35 AM
I set my barrels to the go gauge and then back off a frog's whisker before tightening the barrel nut. Whatta Hobby!

jpx2rk
03-17-2024, 07:09 AM
Lots of people use the go gage, and then add one layer of scotch tape to the base to make a no go gage, so the difference is only .003-4 IIRC. I usually buy the go & no go gages as a set, but that's just me.

charlie b
03-17-2024, 07:53 AM
I've only set two barrels. One I set with go/no-go gages and one with a new case and packing tape. Both work just fine.

When using the gages I set it so the bolt would easily close on the go and then checked to make sure it would not on the no-go. When checked with new brass this resulted in a fairly tight chamber.

Dave Hoback
03-17-2024, 08:24 AM
It’s typically.004”. I’ve never used a NoGo Gauge. In the past I just used the piece of tape trick. But now I use stainless shims I made with the Go gauge.

PhilC
03-17-2024, 09:13 AM
Go gauge and a single piece of scotch tape trimmed closely to case head diameter.

hal9000
03-17-2024, 03:34 PM
I've seen the tape trick online. Thanks for the validation on that.... So it sounds like the range is 0.003-0.004" between go and no go. With the thread pitch on savage barrels it might be hard to tweak to a smaller tolerance than that without a lot of fiddling, but assuming it's possible does it make sense to try to adjust things so the headspace is towards the loose or tight side, or right in rhe center of that tolerance? I'm just wondering if it would impact accuracy, case longevity, or anything else.

Or maybe im just overthinking it, which is also my style!

Dave Hoback
03-17-2024, 08:37 PM
Accuracy typically favors tighter. But to be honest, it really won’t make a bill o’ beans difference for 99.9% of shooters. I made up a .003” shim for mine and the bolt handle won’t even barely come down on it. Although, I’m chambered for 260AI and have a light crush fit on loaded 260 Remington, before fire forming.

LHitchcox
03-17-2024, 09:15 PM
I only bought a no go gage for my first swap. After that I realized what some of the guys above have posted that a no go is not necessary. I usually set minimum headspace by snugging up the go gage.
When you tighten the nut, it adds a couple of thousandths. I check for excess headspace by adding scotch tape to the back of the go gage. The bolt shouldn't close on two layers of tape.

Robinhood
03-17-2024, 09:53 PM
a pair if scissors and a soda can will yield good sized shims. After doing close to 100 of them I have found having the nogo makes things very simple.

GaCop
03-21-2024, 07:30 AM
I set my barrels to the go gauge and then back off a frog's whisker before tightening the barrel nut. Whatta Hobby! Pretty much the way I do it.