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Posted: 4/15/2006 7:41:58 AM EST
If so, did you check headspace first?

From what I understand the springfields and any others with a GI spec barrel/ chamber have a lot looser headspace than a commercial .308 barrel. Yet I'm imagining some have fired commercial ammo, winchester, rem, PMC, etc etc, without any problems. But maybe not. Maybe everyone with a GI spec barrel / chamber but surplus or some kind of 7.62 ammo.

I know this has probably been done before, but will those with experience please respond? Thank you very much.
Link Posted: 4/15/2006 8:16:06 AM EST
[Last Edit: 4/15/2006 8:16:45 AM EST by cookhj]
i've fired remington 180gr SP in my M-1 Garand with no problems.

ETA - i didn't check the headspace for it either.
Link Posted: 4/15/2006 9:48:00 AM EST
IIRC the SAAMI .308 Go gauge is 1.630 and the NATO Go is 1.632

The SAAMI No Go gauge is 1.634 and the NATO No Go is 1.636

The SAAMI Field gauge is 1.638 and the NATO Field is 1.640

So there is a .002" difference across the boards.

But no, I have fired only surplus through all of my milsurp C&R and M1A's.
Link Posted: 4/15/2006 10:08:19 AM EST

Originally Posted By operatorerror:
IIRC the SAAMI .308 Go gauge is 1.630 and the NATO Go is 1.632

The SAAMI No Go gauge is 1.634 and the NATO No Go is 1.636

The SAAMI Field gauge is 1.638 and the NATO Field is 1.640

So there is a .002" difference across the boards.

But no, I have fired only surplus through all of my milsurp C&R and M1A's.



I think your numbers are a little off. At least according to the tacked threads. A field saami is the same as the no go for an M14. But the spirit of your thread is taken. It's not a whole heck of a lot of difference. I'd probably feel better if I gauged it. I don't have any however.

Please others, keep posting!
Link Posted: 4/15/2006 10:20:01 AM EST
[Last Edit: 4/16/2006 11:21:45 AM EST by operatorerror]

Hmmm. Another .002". I got my numbers from the FAL Files (unless I'm remembering them wrong) but I had never seen the tacked thread here before. Are the M14 headspace figures different from the NATO numbers that I have? Or are NATO headspace figures different from M14 headspace specs?
Link Posted: 4/15/2006 11:00:57 AM EST
I've shot Winchester White Box in my Poly, which gauges exactly at 1.634, which is .308 commercial NOGO, with no problems at all. 1.634 is also NATO GO IIRC.

I do NOT plan to shoot any of the new super-duper "magnum" commercial .308 loads in the gun, but it should be okay for standard weight bullets at standard velocities.
Link Posted: 4/15/2006 11:05:25 AM EST
While the 7.62 chambe is 'loose' compare to the 308WIN chamber... the thing one would really need to worry about is the pressure.

.308 Winchester
Maximum: 62,000 psi
Maximum Proof Pressure: 89,000 psi

7.62 x 51mm NATO
Maximum: 50,000 psi
Proof pressure: 67,500 psi


Any well constructed rifle does not fail outright due to pressure problems. It'll take time and other factors to be involve before it fails. The most notable would be a weak action (ie Mauser), which I don't feel is the case for a M1A/Garand action. If a rifle is well taken care of and not 'used and abused', IMHO... it'll take 308win rounds without issue, since most commerical ammo are never loaded to full SAMMI spec. BUT if that's all you planning on shooting, maybe a swap to a commerical 308win barrel would be more insurance for yourself.

The only KB that I read into is the report by Dr. Bruchey funded by FA. And the failure was actually from bad treatment of the barrel resulting in more than usual stress factures around the chamber which resulted in the KB.

My barrel is marked 7.62mm and not .308win, but I generally shoot mil-surplus through my M1A... just because it's cheaper than anything else out there. But every once in a while I would dump a box or two of commerical through it just to use it up.

When it comes down to it... how safe do you feel?

~nb
Link Posted: 4/15/2006 12:09:13 PM EST

Originally Posted By NewbieDave:
While the 7.62 chambe is 'loose' compare to the 308WIN chamber... the thing one would really need to worry about is the pressure.

.308 Winchester
Maximum: 62,000 psi
Maximum Proof Pressure: 89,000 psi

7.62 x 51mm NATO
Maximum: 50,000 psi
Proof pressure: 67,500 psi


Any well constructed rifle does not fail outright due to pressure problems. It'll take time and other factors to be involve before it fails. The most notable would be a weak action (ie Mauser), which I don't feel is the case for a M1A/Garand action. If a rifle is well taken care of and not 'used and abused', IMHO... it'll take 308win rounds without issue, since most commerical ammo are never loaded to full SAMMI spec. BUT if that's all you planning on shooting, maybe a swap to a commerical 308win barrel would be more insurance for yourself.

The only KB that I read into is the report by Dr. Bruchey funded by FA. And the failure was actually from bad treatment of the barrel resulting in more than usual stress factures around the chamber which resulted in the KB.

My barrel is marked 7.62mm and not .308win, but I generally shoot mil-surplus through my M1A... just because it's cheaper than anything else out there. But every once in a while I would dump a box or two of commerical through it just to use it up.

When it comes down to it... how safe do you feel?

~nb




Hmmmm.... that does make sense. I don't know if I've ever seen it that way. The pressures that is. I doubt WWB and such is at Saami limits though. Or UMC etc etc. There are some pretty hot commercial loadings out there for hunting.

That was a pretty good post for someone named newbie. And I appreciate the input.

I'm sure I'll shoot some surplus due to price, as long as I can find it. But I'm sure I'll be shooting some WWB etc, etc. And maybe a mild hunting load or two.
Link Posted: 4/15/2006 2:13:33 PM EST
Anybody else got some experience with this?
Link Posted: 4/15/2006 3:10:49 PM EST
Link Posted: 4/16/2006 10:06:27 AM EST
Link Posted: 4/16/2006 11:24:45 AM EST
[Last Edit: 4/16/2006 4:55:12 PM EST by operatorerror]

Originally Posted By Chuck:
Please stop quoting the previous messages!

These are all together (this is called a thread) and we can all see what's going on. Quoting just slows the reading process. If you need to quote a sentence for clarification please do so, but quoting complete messages (and sometimes the one immediately above!) is unnecessary.

-- Chuck



Sorry about that.

So do you know what the NATO headspace gauge measurements really are? I have read a bunch of conflicting info on this site and the FAL Files.

Or are the headspace specs for an M14 and a FAL different?

Here's what I have so far.

1.630 - SAAMI Go
1.632 - NATO Go (from the FAL Files)
1.634 - M14 Go / SAAMI No Go
1.635 - NATO Go (from Cruffler and 303British.com)
1.636 - NATO No Go (from the FAL Files)
1.638 - M14 No Go / SAAMI Field
1.640 - NATO Field (from the FAL Files)
1.6405 - NATO No Go (from Cruffler and 303British.com)
1.6445 - M14 Field
1.6455 - NATO Field (from Cruffler and 303British.com)

I also have:

1.6315 - NATO 7.62 Min
1.6400 - NATO 7.62 Max

And a couple of other oddball measurements that I have picked up from various sources.

I am so confused.
Link Posted: 4/16/2006 2:03:28 PM EST
Sorry Chuck, I didn't know it was such a problem.

Opratererror, you're funny.

Also, that would be confusing. Maybe they are different.
Link Posted: 4/16/2006 5:35:13 PM EST
OpErr, your purple and green numbers are the ones I've been using as "correct."
Link Posted: 4/16/2006 7:36:54 PM EST
I've shot 150 grain hunting loads in my M-1A, HK 91 and my FAL with no problem whatsoever, BUT in general I use mil spec ball, and use commercial for hunting deer only.
Link Posted: 4/16/2006 9:36:08 PM EST
[Last Edit: 4/16/2006 9:37:34 PM EST by operatorerror]
I'm thinking that the Blue NATO numbers I listed above just might be for full auto 7.62 weapons.
Link Posted: 4/17/2006 5:47:20 AM EST
Only problem I ever had was with Federal GM match. Reloaded the cases, light, the first two rounds fired resulted in casehead seperations.Combination of soft brass and a generous mil-spec chamber.
The chamber would swallow a no-go, but not a field. Had it re-barrelled before I knew better.
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