M305 and Tula ammo kaboom

if the extractor fits over the rim on the gauge, it shouldn't matter about the spring and oprod being installed, you ease it shut on the gauge, it eithers closes or it doesn't.

I typically load the gauge onto the bolt face under the extractor claw then hold it in position as I ease it into the chamber.
 
Looks like a out off battery fire, judging on the lack of primer or damage to the rifle.

Ether a slam fire from a soft/shallow primer or stuck firing pin. I doubt its headspace because if the bolt was locked the bolt face would of supported the primer and steel case ammo is stronger than brass.
 
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haven't we about chewed all the meat off this old bone?-after 85 posts and all kinds of speculation we all know what the answer was, where elp stands, and MOVE ON-mods, how ABOUT U GET OUT YOUR SHOVELS AND bury this thread?
 
t-star said:
haven't we about chewed all the meat off this old bone?-after 85 posts and all kinds of speculation we all know what the answer was, where elp stands, and MOVE ON-mods, how ABOUT U GET OUT YOUR SHOVELS AND bury this thread?
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No need to be rude about it lol.
 
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That's intense.

I strictly run US M80 or Turkish MKE NATO spec M80 ball out of my 1986 vintage M1A. Never an issue.

I only run Russian made ammo out of my Bulgarian Makarov (9x18mm) and AK 74 (5.45x39mm). Also never an issue.
 
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I talk to 5 weapons techs today.. showed them the picture without first telling them the story... every one of them said its a head space issue. After telling them the story on the gauges they were blown away anyone would advocate this is an ammo issue.. and pissed off anyone would say its safe to fire a rifle with that much excessive headspace. One of the senior techs stated that if a tech signed off on a rifle with a gun headspacing over a no go in non war condition and this happened that techs career would be done
 
LordEvilPepper said:
I talk to 5 weapons techs today.. showed them the picture without first telling them the story... every one of them said its a head space issue. After telling them the story on the gauges they were blown away anyone would advocate this is an ammo issue.. and pissed off anyone would say its safe to fire a rifle with that much excessive headspace. One of the senior techs stated that if a tech signed off on a rifle with a gun headspacing over a no go in non war condition and this happened that techs career would be done
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I take back my statement after looking at things more in depth, I missed the part about the Primer set back :redface:

I blame it on a long day at work :p
 
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LordEvilPepper said:
I talk to 5 weapons techs today.. showed them the picture without first telling them the story... every one of them said its a head space issue. After telling them the story on the gauges they were blown away anyone would advocate this is an ammo issue.. and pissed off anyone would say its safe to fire a rifle with that much excessive headspace. One of the senior techs stated that if a tech signed off on a rifle with a gun headspacing over a no go in non war condition and this happened that techs career would be done
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Correct. Headspace is the issue and was likely exacerbated by crappy steel cased ammo that couldn't stretch without splitting.
 
Dsiwy said:
Looks like a out off battery fire, judging on the lack of primer or damage to the rifle.

Ether a slam fire from a soft/shallow primer or stuck firing pin. I doubt its headspace because if the bolt was locked the bolt face would of supported the primer and steel case ammo is stronger than brass.
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What is it with "out of battery" that seems to be the go-to explanation for every single firearm issue seen on the Internet. The vast majority of people haven't got the first clue what an out of battery detonation is or what it would look like but yet they are still proclaiming every rifle failure just must be an out of battery explosion.

For those not paying attention, an out of battery explosion means the bolt was not engaged with the locking lugs. Hence the term "out of battery". In the event of a bolt not engaged with the recoil lugs, the rifle becomes a blow-back system where equal and opposite forces take over. In a true out of battery explosion, the unlocked bolt would be driven backwards with incredible force and either completely wreck the rifle or exit the rifle and severely injure the operator. At the same time the case would be pulled partially out of the chamber just before it exploded from excess internal pressure.

For the most part out of battery explosions are extremely rare because most rifles are designed so that the firing pin cannot move forward until the bolt is fully locked. Even if the bolt is only partially locked, the rifle will operate normally and so does not result in an out of battery explosion.

In the case of this rifle, excess headspace caused the steel case to stretch when fired. Steel, being less ductile than brass caused the case to split and the ejection forces tore the case head off, leaving the case body in the chamber. As the bullet had left the muzzle and operating pressure were close to normal, the split case head only released a small amount of gas into the receiver. Had this been a true out of battery explosion, the massive gas pressure release out the back of the chamber would likely have resulted in injury to the operator.
 
Nachoninja said:
Got the case out with some magyvering using an eye bolt and some rope and lots of yanking. I already have an forster .308 field guage (1.638") and a 7.62 max guage (1.6455"). The pictures below show how the bolt closes completely on the 308 field guage but doesn't quite close on the 7.62 max guage. I saw some things online that says this is ok but to me if it comes that close to closing without being forced I would think itncould possibly be dangerous to fire?
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The M14 chamber is cut to 7.62NATO spec and not to the commercial 308Win spec. My USGI TRW M14 chamber would never have passed the 308 NOGO gauge, it measured 1.641. However, the 7.62NATO NOGO gauge allows up to 1.6445" and thus it was in spec. Since the op's M14 doesn't close on the 7.62NATO NOGO gauge, it is still in spec. The question is, is the measurement accurate without removing the extractor and ejector from the bolt? Below are measurements for 308 and 7.62 GO and NOGO gauges.

7.62 NATO GO Headspace Gage - length is 1.6355" plus .0003" minus zero

7.62 NATO NO GO Headspace Gage - length is 1.6455" plus Zero minus .0003"

.308 Win GO headspace Gage - length is 1.630" plus .0002" minus zero

.308 Win NO GO headspace Gage - length is 1.634" plus zero minus .0002"

.308 Win FIELD headspace Gage - length is 1.638" or 1.640" (?????)

Note that 308 NOGO gauge is smaller than the 7.62 NATO GO gauge!!

What we have here is a chamber close to max spec and steel cases. The M14 was never designed for steel cased ammo and I would never shoot steel cased ammo in the M14 unless I know it had a tight headspace. Anyway, just my $0.02.

Maybe 45ACPking and/or Tactical Teacher could chime in here and give us some of their M14 expertise here and put this puppy to bed?
 
and what did they head space at?

I did a search back 6 months... all the tulammo .308 case head seperations have been in M305's. M305's are notorious for excessive out of spec head space. excessive head space causes case head separations... see a pattern?
 
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t-star said:
b/c they're completely useless- even in brass form- most normal folks can't reload them and the world would be better off without them
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Yeah, that berdan primed Hirtenberger and Port sure is garbage....you make no sense man.
Excessive headspace causes head separation. Some of the Russian steel case ammo has pathetically thin case walls and thin heads, which can be fine in a .308 chambered commercial rifle that is in spec, but not so fine in a 7.62 chamber that swallows no-go and field gauges.
Section a brass 308 case and see how thick it is in the walls/head. They can take more abuse. Here is a Federal on the Left and a Norma on the right.

Compare that to the blown Tula case.
My Nork is 15thou over 308 min out if the box... probably worse now after a few hundred rounds. This is a gun that I have very little faith in.
 
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t-star said:
you'll see them on the ee or sometimes I run guns can get you 1-the best are trw , but you'll still need someone to lap it in

unfortunately there's a lot of smiths out there that say I DON'T WORK ON NORINCO JUNK" - all you have to do is find one that is- 45 acp king is out of the business, but barney ( tactical teacher, hungry) is still around and he's forgotten more than us will ever know about the m14 platform
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Lapping in a bolt is a piece of cake. You just need gauges, a fired cartridge, a hacksaw, a GI hammer spring, and some valve grinding compound.

Cut the fired case in half, put the spring between the halves to tension the bolt. valve compound goes on the back of the bolt lugs. Use a nail or punch through the extractor hole to turn the bolt in and out of battery. a little goes a long way. Stop frequently and gauge the bolt.

It's not rocket science. Last M14 clinic I went to with Barney, we did one just to show ppl how easy it was.

Any smith who won't work on a norinco receiver and install a GI bolt is likely either not used to working on semi-auto battle rifles, does not know the platform, or has too much other work. If they'll clean a POS rusted Cooey for cash, and they won't do a Norinco, then it's not pride, it's ignorance.
 
LordEvilPepper said:
the case was jammed in the chamber and the head was blown off. if it was an out of battery unsuporter lugs the case should have split no? it would have had to been partialy locked in to get the OP's result... and it would have likely sheered the bolt. this is very similar to when mine had a head space issue and the case head partially separated... big poof in the face, but no pieces flying off.
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No, it was probably at least partially in battery. Likely your floating firing pin touched off an overly soft primer OR it was excessive headspace and weak casings. Tula Ammo is not really meant for an M14 IMHO. Works fine in bolt guns though.
 
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LordEvilPepper said:
if the extractor fits over the rim on the gauge, it shouldn't matter about the spring and oprod being installed, you ease it shut on the gauge, it eithers closes or it doesn't.

I typically load the gauge onto the bolt face under the extractor claw then hold it in position as I ease it into the chamber.
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I would tend to disagree with you. Smiths are taught to remove the Oprod and ejector on an M14 ad you close the bolt slowly, by hand to feel for resistance. The op rod spring tensions is enough to ruin your gauge's calibration over time by slightly deforming the angles at the shoulder of the gauge. You are feeling for resistance, not a hard mechanical stop.
 
Dsiwy said:
and steel case ammo is stronger than brass.
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Not necessarily true, depending how you define "stronger". Steel is harder but less elastic. Brass is softer but tougher (in a Young's Modulus sense). The advantage of brass is that it elastically deforms enough to make a good case seal, then springs back enough to ensure the case is not stuck in the chamber.

Steel works, brass works better.
 
Claven2 said:
I would tend to disagree with you. Smiths are taught to remove the Oprod and ejector on an M14 ad you close the bolt slowly, by hand to feel for resistance. The op rod spring tensions is enough to ruin your gauge's calibration over time by slightly deforming the angles at the shoulder of the gauge. You are feeling for resistance, not a hard mechanical stop.
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good to know.
 
RifleDude said:
The M14 chamber is cut to 7.62NATO spec and not to the commercial 308Win spec. My USGI TRW M14 chamber would never have passed the 308 NOGO gauge, it measured 1.641. However, the 7.62NATO NOGO gauge allows up to 1.6445" and thus it was in spec. Since the op's M14 doesn't close on the 7.62NATO NOGO gauge, it is still in spec. The question is, is the measurement accurate without removing the extractor and ejector from the bolt? Below are measurements for 308 and 7.62 GO and NOGO gauges.

7.62 NATO GO Headspace Gage - length is 1.6355" plus .0003" minus zero

7.62 NATO NO GO Headspace Gage - length is 1.6455" plus Zero minus .0003"

.308 Win GO headspace Gage - length is 1.630" plus .0002" minus zero

.308 Win NO GO headspace Gage - length is 1.634" plus zero minus .0002"

.308 Win FIELD headspace Gage - length is 1.638" or 1.640" (?????)

Note that 308 NOGO gauge is smaller than the 7.62 NATO GO gauge!!

What we have here is a chamber close to max spec and steel cases. The M14 was never designed for steel cased ammo and I would never shoot steel cased ammo in the M14 unless I know it had a tight headspace. Anyway, just my $0.02.

Maybe 45ACPking and/or Tactical Teacher could chime in here and give us some of their M14 expertise here and put this puppy to bed?
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You said it all for me. Saves me a pile of typing! :cool:

I have no experience with steel cased ammo... what do I know? I'm just a reloading competitive shooter! I ain't an engineer nor am I a gunsmith or a Wpns Tech/Gunnery Sgt who built these babies their whole career!

Stay safe out there! :wave:

Barney
 
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