Gunsmithing HELP! Wrong "GO" gauge from Forster...

[Wannashootit]

So, I fucked up last week and ordered a field gauge with my fat fingers instead of the "go" gauge I wanted for my 7-08 Savage re-barrel.

Ordered the correct gauge from Brownells, comes a couple of days ago in the factory sealed little plastic baggie clearly saying "..308...7mm.-08....243, etc.".

Get the factory barrel off last night ( a real bitch), start screwing the action on the new barrel, and tear open the baggie for the headspace gauge.

Pull out the little plastic box with the gauge in it and have a fucking shitfit...it's a <span style="font-weight: bold">.223</span> gauge! How the hell does that happen?

Aside from me calling Forster tomorrow and giving them shit (it's not Brownell's fault, the bag was incorrectly marked at the factory), I was wondering if I can FL size one of my cases and use that as the "go" gauge...
I don't shoot factory ammo at all, and I've read of guys doing this before. I realize that SAAMI specs are best and I'd prefer to do it with the go gauge, but have time set aside TODAY to do this project.

Is a FL sized case satisfactory to set the headspace?

I could always use the SAAMI spec field gauge-perhaps in conjunction with a piece of tape on the FL sized case- to verify I don't have excessive headspace.

 

[shoot4fun]

Re: HELP! Wrong "GO" gauge from Forster...

Using a case is not the best method and leaves too much room for error. A field gauge should be .0010" over zero headspace and a No Go is .005" over, so a piece of tape might work.
Bottom line is that you will need the proper Go Gauge to do the job 100% correct.

 

[Wannashootit]

Re: HELP! Wrong "GO" gauge from Forster...

Agreed it's best, no argument there.

But, I've read (here,and elsewhere), that using the FL sized brass outta my die may be better for brass life since the headspace is set "custom" to my dies and won't overwork the brass.

Now, granted this is a new barrel. But, I had no issues with brass life or proper headspace from the dies I've been using with the factory barrel that's being replaced?

 

[bohem]

Re: HELP! Wrong "GO" gauge from Forster...

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">A field gauge should be .0010" over zero headspace and a No Go is .005" over, so a piece of tape might work. </div></div>

That's not correct and the sets are different over various cases. A 30-06's GO, No Go, Field are not the same setup as a 223 or a 338LM.


To the OP -

You can do it, it's been argued ad nauseum, and it's something that professionals did for many years and some still do with oddball cases.

If you want to FL size a piece of brass and chamber to it, my approach is to push the chamber another 0.001-0.002" on that FL sized brass to give you "feeder space" in a tac/field type rifle. For BR work, however tight you'd like to make it is your decision and people do all kinds of stuff in the quest for smaller agg's.


Done right, you can chamber it that way if you'd like and there's no safety issue just the question about how it will cycle factory ammo. If you're not shooting factory much then I really don't see the issue with using the brass.

I use 20lb paper to double check and also ZigZag as it tends right about 1/2 thousandth on the cig paper.

 

[Wannashootit]

Re: HELP! Wrong "GO" gauge from Forster...

Thanks.

Since I do have the field gauge (I was going to send it back, but seems it would be useful now), as long as it won't close on the field gauge after setting with the FL size brass I know I'm not in the "danger" zone...

If a piece of tape on the brass results in the bolt not closing as well, I think I'll be gtg.

I understand that advice given here and elsewhere on the 'net should always be the "correct" way...

Given the huge size difference between the .223 and the .308 I'm kicking myself in the ass for not noticing it even before opening the baggie. Should have seen it...

Edit to add..

I do have the Hornady headspace gauge. I'll check the headspace on some new, unfired brass vs. my FL sized brass first as well.
The die is set to bump .002 from fireformed, but that was with the <span style="font-style: italic">old</span>barrel/chamber.

 

[shoot4fun]

Re: HELP! Wrong "GO" gauge from Forster...

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bohem</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">A field gauge should be .0010" over zero headspace and a No Go is .005" over, so a piece of tape might work. </div></div>

That's not correct and the sets are different over various cases.
</div></div>
Hmmm. The info came from Dave Kiff at PTG. Did I misunderstand him?

 

[bohem]

Re: HELP! Wrong "GO" gauge from Forster...

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: shoot4fun</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bohem</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">A field gauge should be .0010" over zero headspace and a No Go is .005" over, so a piece of tape might work. </div></div>

That's not correct and the sets are different over various cases.
</div></div>
Hmmm. The info came from Dave Kiff at PTG. Did I misunderstand him?

</div></div>

I think you are misunderstanding him. Go, No Go, then field.

No Go on a 30-06 is Go+.006 but the Field is Go+.008 and as it's been explained to me the Field is a military armorer thing meaning "It closes on No Go, but is it safe for Field use"

And I'm not saying that Dave explained it incorrectly, but he was likely telling you about a particular chamber when he gave you those values, they're not universal across calibers or manufacturers.

I have a 6.5x47L set that was setup for medium range BR and the No Go is only 0.001" over Go, my 6.5CM setup is GO and GO+.003 for the No Go and my 30-06 Go from PTG is 0.001" LONGER than the Go that I have from JGS.

 

[shoot4fun]

Re: HELP! Wrong "GO" gauge from Forster...

bohem,
I was referring to the gauges for 308 Win based cases like 243, 7mm-08, 260, etc.
Those numbers were what he gave for that. Based on the fact that the OP is trying to HS a 7mm-08 barrel, I would think my numbers would be correct.
My understanding for the gauges for his caliber should be:
Go Gauge is set to zero headspace
No Go is .005 longer
Field is .0010 longer
Field is safe but not ideal. My 7MM08 GAP rifle was just measured by Accurate Ordnance and came in at 8 thou. They said that was safe eventhough the no go gauge closed on it.

 

[bohem]

Re: HELP! Wrong "GO" gauge from Forster...

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: shoot4fun</div><div class="ubbcode-body">bohem,
I was referring to the gauges for 308 Win based cases like 243, 7mm-08, 260, etc.
Those numbers were what he gave for that. Based on the fact that the OP is trying to HS a 7mm-08 barrel, I would think my numbers would be correct.
My understanding for the gauges for his caliber should be:
Go Gauge is set to zero headspace
No Go is .005 longer
Field is .0010 longer
Field is safe but not ideal. My 7MM08 GAP rifle was just measured by Accurate Ordnance and came in at 8 thou. They said that was safe eventhough the no go gauge closed on it. </div></div>


Field is longer than No Go right? The way the first statement of yours seems to read is that it's Go, Field (= Go + 0.001) and No Go (= Go+.005 or Field +.004)

That's how I was reading it, if that's not what you meant then my mistake.

Acc Ord assessment is right. Go plus 8 is hefty, but if it isn't cutting heads of the cases and you mostly neck size only then you'll get decent brass life without having too many issues with brass.

 

[shoot4fun]

Re: HELP! Wrong "GO" gauge from Forster...

Yea, Field is longer than No Go. Basically up .005 for each gauge.
David is always right. He is one helluva gunsmith!
As for my brass, since I know what to work with I can set my dies accordingly. And yes I mostly do neck size.

 

[338RUM runner]

Re: HELP! Wrong "GO" gauge from Forster...

I think you have to many zeros.Field .010 and not .0010
GO .000
NO GO +.005
FIELD +.010

 

[shoot4fun]

Re: HELP! Wrong "GO" gauge from Forster...

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: xp100man</div><div class="ubbcode-body">I think you have to many zeros.Field .010 and not .0010
GO .000
NO GO +.005
FIELD +.010 </div></div>

First zero is tenth, second hundredth and third is thousandth.
Find the answer here:
http://www.factmonster.com/ipka/A0881929.html

If you want your headspace in hundredths stay on the opposite side of the line from me

.

 

[smschulz]

Re: HELP! Wrong "GO" gauge from Forster...

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body"> (it's not Brownell's fault, the bag was incorrectly marked at the factory), </div></div>
No but they will make it right.
I would call Brownells.
Let them deal with the factory.
I had a similar issue and they took care of it right a way.

 

[bronco_buster]

Re: HELP! Wrong "GO" gauge from Forster...

It's your rife do what you want.

Here's what I mean.

My 6BR's are headspaced with a piece of my resized brass. It produces a very stiff throw on a GO and complete stop on a NOGO. But I could care less about SAAMI on those rifles because they will never eat anything except for my reloads from my dies. I did it that way to squeeze accuracy out of the system. If you reload, and will NEVER use factory ammo, then you can set the headspace to whatever you like. You don't have to headspace it to be compatible with any off the shelf ammo. My FAL's on the other hand, will get fed surplus from all over the world, maybe a box of Win or Rem, but never a reload. I have to use all the gages to assure that the rifle is in spec and safe, while tolerant enough to eat anything. But, we're talking a 1-5 MOA platform in a battle rifle.

 

[338RUM runner]

Re: HELP! Wrong "GO" gauge from Forster...

shoot4fun
.001= 1 thou
.002
.003
.004
.005
.006
.007
.008
.009
.010= 10 thou
.100= 1 tenth of inch

 

[shoot4fun]

Re: HELP! Wrong "GO" gauge from Forster...

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: xp100man</div><div class="ubbcode-body">shoot4fun
.001= 1 thou
.002
.003
.004
.005
.006
.007
.008
.009
.010= 10 thou
.100= 1 tenth of inch </div></div>

Well duh!
It took me a minute to figure out what you were saying. I had it as one thou and meant to write ten thou. And I thought I had it all figured out

.
Thanks for setting me straight.

 

[338RUM runner]

Re: HELP! Wrong "GO" gauge from Forster...

Now can we shoot together. Would be fun to shoot with some of the Hide members.

 

[fdkay]

Re: HELP! Wrong "GO" gauge from Forster...

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: shoot4fun</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: xp100man</div><div class="ubbcode-body">shoot4fun
.001= 1 thou
.002
.003
.004
.005
.006
.007
.008
.009
.010= 10 thou
.100= 1 tenth of inch </div></div>

Well duh!
It took me a minute to figure out what you were saying. I had it as one thou and meant to write ten thou. And I thought I had it all figured out

.
Thanks for setting me straight. </div></div>
So, what is one hundredth of an inch?

ETA
Nevermind, looked it up. Was never a math guy. A real duh moment for me also.
Arbitrary bullshit ten thousandths is the same as one hundredth.

I sure wish they would have considered 100 dollar bills the same as ten thousand dollar bills when I bought my car.