So as I have posted in a couple threads I just recently picked up a slightly used AI AX 308 from the PX. I have only put 30 rounds down the barrel so far and it shot really great, but since I already had some GO and NO GO gauges made by PT&G I figured I would check headspace on the barrel anyway. It failed the NO GO gauge test the bolt will close on it so I ordered a FIELD gauge to see if it will pass it. I am pretty sure it will pass the FIELD gauge test because it just barley closed on the NO GO gauge (and yes I did make sure the barrel was installed correctly) I ordered a 6.5CM barrel for it, installed it and it would not close on the NO GO gauge. Do other people check headspace when changing AI barrels? If so what brand gauges do you use? I think this it great rifle and I don't mind spending money on top tier shit, but AI is fucking smoking crack if they think one GO or NO GO gauge is worth $432.66.....LOL WTF is it made out of Unicorn dust or something?
- Thread starter Steel+Killer
- Start date
I feel like I heard ai spec barrels are long and will fail a no go but pass a field so as to ensure no matter what mud or crap gets in the chamber it has that smidge of extra space to ensure reliability.
Just think of it as partially Ackley improved and you can now load more powder 
AI gauges are of course going to be AI priced! Get some Manson or Forster gauges. A dried cat turd would be a better representation of accurate headspacing over PTG’s crap these days.
Considering it’s designed for serious work a big longer headspace isn’t a big deal.
I always check brand new barrels for headspace, yes. After the initial check, then I never need to check again on that barrel no matter how many times it's taken on and off.
308 with factory ammo, no need to worry about GO + .004. And if you're handloading brass that's been fired in that chamber, just do your normal 0.002" FL Size shoulder bump to prevent any future case head separation. Measure a fired case compared to a virgin case, if your shoulder is growing 0.004" or less, you should be ok. If it's growing something crazy like 0.010" then you might run into trouble fast.
My first 6.5x47L barrel from EuroOptic, along with another aftermarket barrel from a known 'smith, both had too long of a headspace. It was before I had a GO Gauge, so I figured it out because virgin brass wouldn't extract once chambered...the case was so much shorter (something like 0.007") that the extractor wouldn't reliably ride over the rim. If I timed out at the end of a stage and cycled the bolt back, the live round would remain in the chamber...NOT COOL haha
Last point...your PTG gauges might be total crap. Or they could be ok. Like @AIAW suggests, you might want to look into another brand. Beyond what he said I also recommend JGS.
308 with factory ammo, no need to worry about GO + .004. And if you're handloading brass that's been fired in that chamber, just do your normal 0.002" FL Size shoulder bump to prevent any future case head separation. Measure a fired case compared to a virgin case, if your shoulder is growing 0.004" or less, you should be ok. If it's growing something crazy like 0.010" then you might run into trouble fast.
My first 6.5x47L barrel from EuroOptic, along with another aftermarket barrel from a known 'smith, both had too long of a headspace. It was before I had a GO Gauge, so I figured it out because virgin brass wouldn't extract once chambered...the case was so much shorter (something like 0.007") that the extractor wouldn't reliably ride over the rim. If I timed out at the end of a stage and cycled the bolt back, the live round would remain in the chamber...NOT COOL haha
Last point...your PTG gauges might be total crap. Or they could be ok. Like @AIAW suggests, you might want to look into another brand. Beyond what he said I also recommend JGS.
Yes! I can’t believe I left JGS out, damn.
I bought these gauges about 3-4 yrs ago they have served me well on my Remage builds(I think ), but I did just order a 308WIN and 6.5 CM Field gauges made by Forster.
), but I did just order a 308WIN and 6.5 CM Field gauges made by Forster. The only reason I bash on them is because they screwed up 2 reamer orders on different occasions, and burned me on headspace gauges also. Many others here have had the same QA issues with them.
I sold a “spare” AXMC I had many years back and the buyer ran PTG gauges in it... swore I sold a rifle with a setback lock ring in it. Took a lot of convincing to have him buy non-PTG gauges... outcome was an inbound apology afterwards. It wasn’t necessary because I don’t blame him one bit. You are supposed to be able to trust these tools!
I sold a “spare” AXMC I had many years back and the buyer ran PTG gauges in it... swore I sold a rifle with a setback lock ring in it. Took a lot of convincing to have him buy non-PTG gauges... outcome was an inbound apology afterwards. It wasn’t necessary because I don’t blame him one bit. You are supposed to be able to trust these tools!
Thanks for the heads up I thought PT&G made top notch shit I guess I was lucky I couldn't find their FIELD gauges in stock anywhere. Like I said in the first post I am pretty sure the 308 barrel is GTG besides I am probably going to shoot the 6.5CM barrel mostly anyway.
I have a Forster GO gauge and a Mo's headspace gauge for brass. My AINA 308 barrel reads +.002" and my Tooley 260 barrel also reads +.002" and fired brass reads the same on the Mo's gauge.
SAAMI specs for a 308 are 1.630" min 1.640" max
Go is 1.630"
No go is 1.636"
Go is 1.630"
No go is 1.636"
I know this is an older thread, but I recently picked up an axsr in 300 nm and wanted go/no go (haven't shot it yet, but like to check prior). Only place I could find was PT&G (unless Forster etc. take custom orders which I may have overlooked). I've personally never had an issue on several calibers of their gauges with multiple actions (first AI though), but had the same question as the OP when I saw the AI gauge's cost. The gauges haven't shipped, and who knows when they will with this crazy supply chain bs, so I'm a little concerned on the no go side based on previous comments (PT&G doesn't offer a field gauge on their site). So my question is if there's a consensus that PT&G are GTG now from being in tolerance, or are there still issues? If still issues, does anyone recommend another route for gauges?? Thanks
I would contact JGS, Manson or Forster before I would risk a PT&G order again. That’s just me. I’m not sure if their QA had improved any since this thread was originally posted.
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I would seriously read this thread.
Gunsmithing - Pacific Tool & Gauge SUCKS!!!
It has been my previous experience that companies put items on sale, because they have inventory to liquidate... Apparently, PT&G likes to put items "on sale" that they haven't made yet. 2 months and counting waiting for Howa bottom metal... PT&G can choke on a bag of dicks...that is all.
www.snipershide.com AIAW answered pretty well.
Called Manson today, ships tomorrow. Thanks for the input!I would seriously read this thread.
Gunsmithing - Pacific Tool & Gauge SUCKS!!!
It has been my previous experience that companies put items on sale, because they have inventory to liquidate... Apparently, PT&G likes to put items "on sale" that they haven't made yet. 2 months and counting waiting for Howa bottom metal... PT&G can choke on a bag of dicks...that is all.
AIAW answered pretty well.
A few years back I borrowed a friend's set of PTG 6.5 CM gauges to check the headspace on a new Tooley chambered AINA 6.5 barrel for my AE MKII. The bolt would not close with the go and no go gauge. I ordered a set of Manson gauges and go figure, the bolt closed on the go gauge and wouldn't on the no go gauge. Can't go wrong with Manson, good choice.
Just think of it as partially Ackley improved and you can now load more powder
Ackley-ishAI and Hornady will be on shortly with a new advertisement.
My AT barrels have longer HS than any other rifle I’ve ever loaded for, .004” longer than my TRG. I recently got a 6.5CM prefit and its .002” longer than the AI 6.5 CM factory barrel, but when I measured everything out and compared to the SAAMI schematic it’s right in the middle of the allowable range.
I’ve never checked headspace with probably 10-15 ai, dt and 700 clone prefit barrels.
is that really necessary
is that really necessary
I don’t even own Go’s and No Go’s. So obviously I don’t make it a hardcore practice to check past DT or other Prefits. And haven’t with my AI
However, I usually try a shoot factory round and see how much the headspace increases just to know that barrel isn’t jacked.
I have purchased a brand new Barreled action in the past from a reputable smith and after some frustration found that it was reamed too short. So it does happen
However, I usually try a shoot factory round and see how much the headspace increases just to know that barrel isn’t jacked.
I have purchased a brand new Barreled action in the past from a reputable smith and after some frustration found that it was reamed too short. So it does happen
On my newest barrel, the first firing will stretch the case .009”
Do we want the case to stretch that much? I like my cases to stretch less.
Bought a spare Proof 6.5 CM barrel, got a Proof 308 Win barrel on back order with Europtics, all juiced up to do barrel swaps on my brand new AT rifle and enjoy that "capability". Then I did the unforgiveable sin, I read the AT instruction book and its specifies I must have AI head space gauges. Take a look online and at $500 a pop, for two calibers (GO & NO GO sets each), another $2K out the window. So this quick barrel change option has become a quick bank robbery in progress.
My, obviously uniformed question is this: Will Forster Gauges suffice ..a Go, No Go and Field Gauge set be satisfactory for the only calibers I shoot ..6.5 Creedmoor & 308 Win ?
THank you in advance.
My, obviously uniformed question is this: Will Forster Gauges suffice ..a Go, No Go and Field Gauge set be satisfactory for the only calibers I shoot ..6.5 Creedmoor & 308 Win ?
THank you in advance.
Yes, any go gauge should match others close enough to be fine and functional.
A layer of scotch tape or two on the back of a go makes it ~4 thou longer and thus a nogo.
Yup its supposed to be a standard so in theory it shouldnt matter. Any reputable company will do.
Lots of people use the scotch tape hack
Lots of people use the scotch tape hack
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