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  #21  
Old 07-04-2012, 12:50 AM
jarheadteacher jarheadteacher is offline
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Replies to thoughts and questions to my post:
Spankybear, lol, perfect single answer response.
I do not know if he was single loading by inserting into the magazine or letting the bolt slam home a loose round on top of the magazine.
To my eyes the receiver was not damaged, just the magazine well.
I did not know the man previously so I have no access to further pics such as the bolt face & breach.
Am I sure it was his hand loads? No, I am just sharing what he said to me....
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  #22  
Old 07-04-2012, 12:54 AM
jarheadteacher jarheadteacher is offline
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Replies to comments, page 2.
I do not know if he was using Federal primers.
deagle2008, I sent you a private message.
Yes, the old man is ok and said he will get a new stock and keep shooting.
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  #23  
Old 07-04-2012, 01:59 AM
GGaskill GGaskill is offline
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IMR3031 is a little fast for .308W in my opinion. A max load for some bullets is compressed and for others leaves room for more powder.

My guess is too much powder; but only a little too much. We all make those mistakes. Some times we get away with them; sometimes we don't.
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  #24  
Old 07-04-2012, 05:46 AM
HughUno HughUno is offline
 
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Default this is a case HEAD failure

(almost certainly) not an overpressure round/re-load.

A case head failure is totally different from a ruptured/broken case (BTW and has nothing to do with headspace).

It could have been this gentleman's reload, but the problem was not the load (and BTW 3031 is absolutely OK for .308).

The problem is that TZ brass/ammo from the early 80's is extremely dangerous.

Frankly, I am a bit surprised that this person who "spoke very knowledgeably about shooting and reloading" and was 70 years old wasn't aware of this. It's fairly common knowledge. You should neither shoot nor reload this.


Last edited by precision40; 07-05-2012 at 02:39 PM.
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  #25  
Old 07-04-2012, 06:16 AM
wesvb wesvb is offline
 
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I see what looks like a deep ejector mark on the picture of the casehead. If it is then the failure was from too much powder in a suspect weak case.
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  #26  
Old 07-04-2012, 08:44 AM
ceresco ceresco is offline
 
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I am always cautious about diagnosing over the phone or assuming evidence is not altered by the event, however.....this looks like a case head failure. I have seen a few and until one lets go 6 inches in front of your face you may not fully appreciate what hot gas at 50,000 psi look like or what it can do. HughUno has this one right, IMO. BTW, IMR 3031 is something of a standard for light bullet .308 loads--and perfectly suitable. While a case head failure is serious anytime, this incident also points out the fact that the 7.62/.308win world is less forgiving than the 30-06 for many reasons. Good Shooting.......

Last edited by ceresco; 07-04-2012 at 08:55 AM.
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  #27  
Old 07-04-2012, 11:47 AM
M14 M14 is offline
 
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ceresco is correct. It is a case failure. Gentlemen, once and for good, with a 'proper' rifle like this, there is no such thing as a slam fire. It is impossible. An extremely high seated primer would not allow the bolt to even go to battery, therefore, the hammer could not lower or strike the firing pin.

This case was fully supported on the case wall, all the way to the rear. The bolt was in battery. The gas blew/cut the primer pocket, which vented the pressure to force the ejector spring and ejector rearward, as it split the case section forward of the head. Then like lightening, the gas found the crack between the ejector that was forced rearward, and the bolt face, then downward. This is evidenced by the bottom of the bolt in the photograph.

The bolt is still in battery at this point in time. You can see the path of the gas has marked it on the front end. It trails rearward on the bottom of the bolt because the pressure also pushed the magazine follower down, letting gas escape rearward on the bolt bottom. There should be gas marks on the bolt lock window also, and the scope mounting threaded hole, on the outside of the receiver. The bolt lock spring probably needs replacing too. When it filled the receiver, it had nowhere else to go except to go into the mag. Thank goodness he was firing single load. A full mag could have been disasterous when it lit off another round or two.

This may indeed be something to do with headspace. The bolt face and the cartridge base, will have limited space between them when in battery. A longer headspace and shorter cartridge, would have allowed the gas to escape more readily between that crack, on this particular scenario.

Either way, if you can get back to him or get a message to him through the range officials, I would not fire that rifle again until checked out by an armorer. He could have etched the chamber, weakened the lugs or bolt, cracked the barrel ring, and all without being visible to the human eye.

Thanks for posting this. A similar event just occurred to a friend of mine, different reason, but same result. He lost much of his hand because of shooting with it supporting the mag. Please do not shoot like this guys, no matter who tells you too. If it is law enforcement, quit, if it is military, go to the brig, just don't do it.

Every test Garand did with the M1 for destructive testing, they all blew out the same way as this did, even the bolt lug and barrel failures. There is a book or articles out there about it, with all the pictures and results, if you search long enough like I did for it. Sorry I cannot recall the name and didn't back-up the file before my computer crashed a few years ago. It is very informative and enlightening....and scary. IIRC, one of them took 31 proof rounds before letting go, and they kept increasing the powder and changing powders with faster burn rates to finally destroy it. Eventually it cracked both bolt lugs and sheared them off. Interestingly enough, there was no set-back in the receiver lugs when the bolt was replaced with a new one. Believe it or not, they put it back together and fired it some more. Heck of a rifle platform.
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  #28  
Old 07-04-2012, 12:17 PM
Paladin601 Paladin601 is offline
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M14, the other rounds would not be touched off, as my AR had a full magazine and the gas pressure just forced them out the bottom of the magazine.

And just as a side note, the blown out magazine sides, popped back into shape, And still works quite well. All parts in th bolt were replaced and the Rifle shoots fine.

Last edited by Paladin601; 07-04-2012 at 07:27 PM.
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  #29  
Old 07-04-2012, 12:22 PM
Eliyahu Eliyahu is offline
 
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Looks like bad TZ 7.62 brass claims another victim! The stuff was sold as scrap on the open market and imported by a long-gone notoriously bad importer and widely distributed.

Eli
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  #30  
Old 07-04-2012, 05:42 PM
lite-box lite-box is offline
 
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Agree with M14 this is a classic casehead failure and the resulting damage is typical for what happens with a M1A-M14. 50,000 PSI can do some amazing things.

I have yet to see a real documented OOB with either a Garand or M1a/M14.
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