Blown out primers, 30M1 Carbine

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SKULLANDCROSSBONES65

New member
G'day
I'm trying to find information about the 30M1 Carbine ammunition and or rifle.
I have come across a issue where 7 of 7 primers come out of the fired cases. These were new factory rounds.
Is this common for this ammo or firearm?
Any ideas what areas to look?
 
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LeverGunFan

New member
That is certainly not normal for the M1 Carbine or any other firearm. There should be some M1 Carbine experts here to help, what vintage was the M1 Carbine and the ammunition? Does this happen to the M1 Carbine with other ammunition? Does the ammunition do this in other firearms?

I have limited experience with the M1 Carbine.... the book "The M1 Carbine Owners Guide" by Ruth and Duff does not have any diagnostics for loose primers. Perhaps an oversize chamber or a batch of brass with oversize primer pockets.
 
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jag2

New member
Seems like every time a shooter has a problem he wants to blame the ammo, usually the primer. In this case you may be right, but we do need much much more info. Ammo brand, used it before, new gun, tried different brand, what do mean by came out? Pushed out, fell out, wasn't there? You get the idea.
 
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SKULLANDCROSSBONES65

New member
G'day
Sorry for the lack of details.
It may be a few weeks before I see the person who Talked to me about this issue.

"Came out" = missing from spent cases.
This is the first time this person has experienced the issue.
Recently acquired rifle. Rifle age unknown.

I was not trying to blame either the rifle or ammo. TFL is a great place to find people with a wealth of knowledge on firearms issues.
 
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T. O'Heir

New member
"...missing from spent cases..." Is not normal. Which rifle makes no difference, assuming it's military vs one of the many civilian copies. Some of which are better than others.
I'd be suspicious that the ammo may not be factory. More likely to be reloads. Blowing primers indicates excessive pressure or bad brass or both. Mind you, in Australia, you might still be seeing some old Chinese ammo. LC 52 is the head stamp on that. Also has Berdan Primers.
What's the brand or ammo and head stamp?
"...Rifle age unknown..." Military M1 Carbines were only made Stateside during W.W. II. There have been Carbines made elsewhere though. Howa in Japan, for instance. Those are pretty decently made though.
The Serial Number will tell you a lot. Each U.S. makers was assigned a S/N range.
Go here. All the links work.
http://www.uscarbinecal30.com/
 
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HiBC

New member
I can't say I know the answer. My impressions:

I'm having a hard time imagining a gun related condition that would cause the primers to fall out. What are the possibilities? Grossly excessive head clearance/headspace? Its hard to imagine enough to let the primer fall out.

Bellmouthed or oversize chamber diameter allowing too much case head expansion/unsupported case?....Maybe. Its conceivable.

Gross overpressure causing case head expansion/loose pockets...certainly could happed.

Remanufactured ammo had the primer crimp removed,thats normal,but the pocket may have been reamed/swaged oversize.

Obscure possibility,some foreign carbine ammo was berdan primed. The pocket dia may be close enough to prime with a boxer primer.That does not mean it will work out well. Look for a pair of small,off center "flash holes vs one about 1/16 in in the center.

In any case,I would not shoot more of that ammo.

Buy a box of known good ammo and try it.
 
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tangolima

New member
I have exactly the same thing happened to me. The problem was the factory rounds, magtech (armscor). The brass was too soft. After one firing, the primer pocket opened up, letting the spent primer drop out. I dumped the brass and went to some other brands of brass for handloading. Never a problem since.

-TL

Sent from my SM-N960U using Tapatalk
 
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Pathfinder45

New member
I was under the impression that semi-automatic rifles were banned in Australia not too long ago. If that's true, then the best thing you can do is to not get yourself implicated in something that could cause you trouble.
Other than that, there is something defective with either the carbine, or the ammo, or both. It's probably the ammo exhibiting dangerously high pressure.
 
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bamaranger

New member
.30 carbine

The .30 M1 carbine operates at very high pressure and I've always been deceived by its modest sized case. A reminder of the fact is to be around somebody shooting .30 carbine in one of the Ruger SA revolvers from back in the day.....concussive.

Still not clear f WHAT rifle we are discussing, it seems implied it is a semi-auto M1 Carbine, but the .30 carbine cartridge was available in the in the old Levermatic, and lever rifles ARE legal down under (I think).

All that said, I have seen primers tossed from an AR/.223 with it's semi action, the brass in question was reloaded and there was no primer crimp. If we are indeed discussing a GI semiauto carbine, I'd think by now, a GI carbine would have been shot a lot, the recoil spring could be due for a change, and the action would be very bang/slam in nature. Enough maybe to drive a primer from its pocket, especially if said ammo did not have a crimped primer.
 
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HiBC

New member
FWIW,SAAMI max pressure for 30 carbine is 40.000 cup . That would be high for a handgun,its moderate for a two lug rotary bolt rifle. Still,I'd follow it. No need to beat up a carbine.

I suspect tangolima nailed it. Magtech /Armscor ammo is fairly common and value priced.

If a person buys some banging ammo,its likely to be Magtech or Aguila.

A production problem could cause dead soft brass to escape,and tangolima had the experience.

For all the suggestions about it being a gun related problem,when I think about "OK,just how does that cause the primer to fall out,? I can't come up with a connection.

It almost has to be an ammo problem. Change ammo.

Regarding 223/5.56 dropping primers: The nature of 223 brass is that it just does not have excessive strength around the primer pocket.
If you hotrod your 223/5.56 reloads,you will get loose primer pockets.

The perceived "benefit" of a few fps can cost you in brass life.

I have read that some match shooters load hot for 600 yds.They just accept the brass is scrap. Others may salvage it,only to find loose pockets
 
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SKULLANDCROSSBONES65

New member
G'day
Pathfinder45 I'll plead the 5th.
Each state has slightly different laws. It's easyst to think of them as banned. It would be like me saying full auto is banned in the USA. Banned? NO. Restricted? Yes.
Under limited conditions they are permitted, i.e. medical or occupational requirement. The property I live on is more than large enough to qualify (500sq miles). I personally might be able to get one under "medical exemption".
This is a subject for a whole new thread. PM me if you want more info.

I have found out that other rounds from the same packet have not had any problems.
 
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fourbore

New member
tangolima said:
I have exactly the same thing happened to me. The problem was the factory rounds, magtech (armscor). The brass was too soft. After one firing, the primer pocket opened up, letting the spent primer drop out. I dumped the brass and went to some other brands of brass for handloading. Never a problem since.

-TL

Sent from my SM-N960U using Tapatalk
Click to expand...

Interesting response. Seems worth a bump up
 
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amd6547

New member
I had the same problem with Magtech.
When I got my CMP Inland, I bought a few kinds of ammo, including Magtech.
While shooting, I had a jam where the bolt didn't go into battery.
I discovered a spent primer in the cam area of the op rod.
Looked at my spent cases, and found a few with missing or loose primers.
No problem with any other ammo.
 
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smee78

New member
Well it sounds like an ammo problem. As it was mentioned I would first try a different brand of ammo and go from there.
 
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T. O'Heir

New member
"...from Brazil..." Yep. Companhia Brasileira de Carthorses. Sold, Stateside, by Magtech(who are not Armscor. That is from The PI.) Probably in Australia too. Approximately 1990 FPS MV. 965 ft.-lbs. ME. No pressure numbers available, but that's not terribly hot and is a bit below max loads for a 110. SAAMI(American spec) says Max pressure is 40,000 PSI for The Carbine. Max loads of IMR4227 run 38,800 PSI at 2,003 FPS. Out of a 20" barrel though. (My Plainfield loves IMR4227.)
"...I'll plead the 5th..." Don't believe 'The OZ' give you that option. None of my business, of course. Our Socialist Rats don't know anything either. snicker.
 
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