.30 Carbine blown out shell case

[JT'sDad]

IAI M1 Carbine has functioned perfectly with several ammo types.
Fired PMC for the first time yesterday and two cases blew out-
First blew out the bottom of the magazine. I did not see the case so I checked the carbine over it looked fine, I put a new mag in and bam- same thing. This time I found the blown case and the first one as well.

I then field stripped the carbine- it looks fine. Put a third mag in of Remington and fired away- no other problems.

Could the PMC ammo be a bad batch? I don't plan on shooting any more of it, but what else should I check? Thanks

 

[10X]

I think you answered your own question.
That looks like bad ammo for thaqt rifle to me. I am surprised, PMC is usually good stuff.

If the rifle worked fine with the later mag of Remington, I don't think you need to worry about anything.

 

[loadedround]

I agree. Looks like poorly made cases.

 

[kanook]

contact PMC and let them know what happened. your ammo could start a recall or you could get some FREE ammo out of it. either way, contact PMC

 

[BBBBill]

Can you detect any bulging in the Remington cases? Check carefully. Those pics look like out of battery fire or unsupported case ruptures to me. Either way, not a good thing. The Remington brass may be just enough stronger to not rupture. If so, then it may be that the gun is at fault and running on the ragged edge every time you pull the trigger.

 

[41022collector]

I have a smithy biz and I see a lot of pieces with blown cases, esp mil-surp from foreign countries stuff.

1. PMC, Brown bear, Silver Bear and Wolf ammo have been a nightmare in many aspects, yes I know it is cheap, but you truly get what you pay for. I would say 70% of the so called malfunctions of pieces into the shop here are caused by crappy so called NEW - reloaded or poorly reloaded ammo.

2. The cases look to me like rear chamber errosion (sometimes expansion pitting in the chamber) or you have something keeping the bolt not to be fully forward, but only shown with cheap ammo. The ammo cases from PMC can have a length issue as well, have seen that more times than I care to admit. No use calling them, they know, trust me they know.

A: You can get a throat and chamber gauge, as well as a head space gauge from Sarco or Numrich gunparts. If the chamber is worn or expansion pitted, you have two choices, hard nickle plating (approx $80 to $125) or buying and install a new or slightly used barrel that you checked all the specs before installing. Plating has one advantage in that the chamber and barrel will damn near last forever. Mil-Surp barrels were made for at best 3000 rounds before they truly show signs of use and abuse (talking .30 carbine here), The Inland and Winchester blue prints for WWII Carbines actually have this as a production note on the prints as a 1 in 1000 Q/A check. I know many carbine shooters that get mil-surp barrels and get them plated and turned no matter what, even new barrels. That whole ounce of prevention Vs. a crap house of cure thing......

B: Especially on a mil-surp military rifle, the better the ammo, the better the experience and performance. I cannot tell you how many times I have had to repair nice old work horses from bad ammo, like that junk that J&G sells, I have yet to see anything from them, ammo, firearms or accessories with so called great savings that did not turn out to be junk and in the end, costs you money for repair, replacement or worse.

If you need some sources for chamber and barrel plating, let me know, I will turn ya on to a cpl good ones.

Regards,
Mike

 

[JT'sDad]

Gentelmen- Thanks for the input.
I stopped by my local gun store today. I took the box of PMC with me and the guy did not like the look of them, primer seat depth in particular. He took three and was going to take them apart and weigh, measure them. I will call him tomorrow and post back on here.

 

[rcmodel]

I would suspect partially out of battery slam-fires.

That can be caused by soft or high-seated primers in a semi-auto.

The primer on the right of the picture appears to be well above the case head.

rc

 

[Badger Arms]

I would suspect partially out of battery slam-fires.

+1 -- Popped primer is indicative that the bolt face was NOT contacting the cartridge when the primer was detnonated. Also, case was not fully inserted into chamber. Doesn't look like the case's fault at all.

Troubleshooting:

1) broken firing pin
2) improperly installed or worn extractor (that might be locking firing pin forward, broken or not).
3) receiver bridge is deformed where the firing pin tail is supposed to go through.
4) improper headapsce

 

[JT'sDad]

I am planning on a trip to the gunsmith to get her checked out, even if ammo is the issue.
Thanks for the great feedback-

 

[JT'sDad]

Just picked up my M1 Carbine from the gunsmith. Carbine is in fantastic shape, the entire problem was with the PMC ammo. Bad powder charge-or load. Gunsmith fired a round through his own M1 Carbine and it blew the case out as well. Obviously I will never buy PMC again- there goes three boxes of ammo- crap. Anyway good to have my Carbine back and to know it was never the problem.

 

[robphillips]

If I had a pic of some pmc ammo I had I would post it. This stuff was so thin that some of it split before firing it. I mean, come on new factory ammo with split cases.
I would have to be awfully desperate to use PMC.