excessive headspace in 7.62 ishapore

B

boostedtt91

New member
i just picked up a 308 ishapore 2a and i bought of box of military brass cased 7.62 nato ammo and bought a 100 rounds of MFS ammo that was marked as 7.62x51 but turned out to be .308 win. i took the gun to the local gunsmith today to get the headspace checked and the bolt closes on both the 308 go and no go gauges. He checked it out and said some of these usually are built with alittle headspace so the gun will shot with dirt and gunk in it.

I went to the range to shoot it and tried shooting both and the brass cased 7.62 shot great with no issues and the steel cased 308 ammo the primer is pushing out when shot. Im not sure if the headspace is causing this or its just cause of shooting 308 win ammo. Either way, the gun does have some excessive headspace, but i dont know how much exactly. Is this a major concern and is there anyway to fix this headspace issue? If i just stick with actual 7.62 nato ammo should i be ok? Any advice would be greatly appriciated.
I have read that it might be possible to change the bolt head to fix the headspace on these, is that true? If so where do i get one.
 
I believe the bolt heads on the .303 enfields were numbered '1', '2', or '3'. If your headspace was excessive with a '1', you moved up to '2', and so on. If you're already at '3' then I don't know what to tell you. This information comes with the disclaimer that it's the best I can remember, may not be entirely accurate. If you don't get any answers on TFL try to cross post this on Gunboards forums as well. i'm sure one of the folks over there would answer this pretty quick.
 
My understanding is that a properly headspaced US 7.62x51 would close on a SAAMI .308 Winchester NOGO gauge, but wouldn't close on the .308 FIELD gauge.

SAAMI headspace for a civilian/commercial .308 rifle.
GO - 1.6300
NO-GO - 1.6340
FIELD - 1.6380

Shop (Military) Gauges

GO - 1.6350"
NOGO - 1.6405"
FIELD - 1.6455"

It would probably be worth it to check it with a field gauge.
 
I have read that the 308 is shorter than the 7.62 so it will close on a.308 no go gauge. To properly check you need a 7.62 specific gauge. Im just guessing thete has to be some excessive headspace to have primers backing out on 308 win ammo
 
All Ishapore Enfields have generous head space since they are made for 7.62NATO. My Ishapore will close on NO GO 308 gauge as well but will not close with one layer of masking tape on the No Go gauge.
 
The bolt will close on a 308 field gauge, if i add a .010 to the field gauge it wont close. Not sure where the exact point of closing and not closing is
 
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The bolt will close on a 308 field gauge, if i add a .010 to the field gauge it wont close. Not sure where the exact point of closing and not closing is
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Is it safe to shoot commercial .308 then? Maybe, but you don't know. It has failed all .308 safety checks. Personally, I'd stick with NATO crossed ammo. I bet you can get most of your money back out of the .308 Win ammo.
 
Until you've figured out the exact headspace I would stop shooting the gun. Excessive headspace to ensure operation under all circumstances is a risk a rifleman in the field takes, as a failure to feed might get him shot by the guy shooting at him from the other side. But for hobby use that risk is excessive; find someone with a field gauge, or start adding shimstock to a no-go and find out where your rifle really is dimensionwise.
 
@TX Hunter
if it is backing the primer out it is not safe to fire !
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TX, this is not necessarily so. On full-house loads, most primers that are not crimped in, will back out under initial ignition, only to be reseated by the case subsequently being thrust back against the bolt face upon the development of the full case pressure.

Weak loads will often fail to re-seat the primer even with acceptable headspace.

Just to clarify...
-SS-
 
Its only backing primers out on this steel cased mfs 308 ammo but isnt with brass cased 7.62 nato ammo. Is it safe to shoot 7.62 nato spec ammo?
 
Your rifle closes on the most generous gauge, a military field gauge. Your head space is excessive, the gun is NOT safe with any ammo.
 
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