348WCF Cases splitting at the mouth

[348WCF]

hope someone here on the board can help with this one....
My father just received a Ruger #3 back from the gunsmith who rebored and chambered it for the 348WCF. He has shot a couple boxes of Winchester factory ammo through the gun(about two weeks ago) and had no trouble.
He took the gun out today and had three cases split at the mouth. These are factory new Winchester 200 grainers, not reloads. Is this a problem with the ammo or the chambering of the rifle? I am not a reloader(yet) so I am relying on the expertise of the folks on the board, any suggestions?
Thank you,
Jim

[Gun Smith]

Because 348 cartridges may be 50 years old on a dealer's shelves, the brass may be brittle. The ones that are not lost can be annealed quit simply when you do start to reload. It is possible that the chamber is oversize at the neck. If you have any sort of micrometer you can measure a fired case against a new one and get an idea of the fired dimension. Post those numbers and someone on the site will be able to tell you if there is a problem.

[Hobie]

Same ammo?

[348WCF]

Hobie,
yes, the ammo is the same. it is some of the commemorative ammo that Winchester ran in 87-88 for the Browning Model 71's that came out then. I am having him see if the ammo was all from the same lot # so we can mike them as Gunsmith suggested.
Jim

[71fan]

Someone else here had a similar problem a few years ago with 348 factory stuff. I want to say Pharmseller, Boreman, or big bear...I can't remember. Whoever it was had located and bought an entire case of ammo and was getting splits. They called Winchester to see about exchanging the ammo and I don't remember what happened after that. Hopefully they'll pop in.

As a side note, I suggest you edit you subject line to read "348 Cases splitting at the mouth" to attract the 348 shooters.

Anyway, you're on the right track. Check the lot numbers on the ammo to see if they are the same, and post those dimensions.

Good luck!

[flatnose]

Out of a pack of 50 new cases, I expect to lose 1 or 2 cases due to splitting at the mouth. I now anneal my brass every first and 3rd firing. I think winchester had a batch or two of brass that was a bit on the brittle side. Had similar situation with the 307 brass as well.
Measure your case neck diameter on the fired brass and compare with the unfired cartridges. The fired brass generally has a 1 thou spring back, so add this to your fired brass diameter.
place a fired and a resized case side by side, and you will notice quite a visible difference between the two. The fired brass grows a lot in diameter.
To increase case life, I mostly neck size only, and bump the case shoulder back a couple of thou on every third loading, or as required.
Neck splits isn't uncommon on the 348.

[Kansas Ed]

Hobie,
yes, the ammo is the same. it is some of the commemorative ammo that Winchester ran in 87-88 for the Browning Model 71's that came out then. I am having him see if the ammo was all from the same lot # so we can mike them as Gunsmith suggested.
Jim

My wifes '71 was purchased along with a box of that exact same ammo probably about 1992 or 1993, and several had case cracks after the first firing. I would lean toward the factory brass of that lot. IIRC, hers were splitting at the neck shoulder junction.

Ed

[mod71alaska]

Someone else here had a similar problem a few years ago with 348 factory stuff. I want to say Pharmseller, Boreman, or big bear...I can't remember. Whoever it was had located and bought an entire case of ammo and was getting splits. They called Winchester to see about exchanging the ammo and I don't remember what happened after that. Hopefully they'll pop in.

As a side note, I suggest you edit you subject line to read "348 Cases splitting at the mouth" to attract the 348 shooters.

Anyway, you're on the right track. Check the lot numbers on the ammo to see if they are the same, and post those dimensions.

Good luck!

Good Morning,

As I recall, the Levergunner who had the case(s) of 348 ammo that split lived in the SE US (and so not Pharmseller or big bear. I don't think it was Boreman, either.) He contacted Winchester and they replaced the 10 box cases with new ammo. My recollection also is that historically some of the Browning/Winchester ammo had bad brass that split. Contact Winchester. I'm sure they will replace your bad ammo with new. Good luck!

[big bear]

Wasn't me. I've got a couple of boxes of that browning commemerative ammo from trades,never shot any of it though. saving it to sell someday to some "collector" so I can buy more powder, primers and bullets!I remember the posting too, it went on for a couple of pages, not one of the ususal 71 suspects though by me recollection. Off to work, have a good day all you crazy guys

[pharmseller]

Not me, either.
My factory fodder is relatively new, and I have had zero issues with it (except, of course, for the price!).
I have heard from several shooters that the commemorative brass was faulty, so I am not surprised.
Find some standard issue factory loads. Gunbroker usually has a few (http://www.gunbroker.com/Auction/ViewIt ... =140304279).


Pharmseller

[Boreman]

Wasn't me either. Case splitting in my experience is pretty rare. I have only had 1 or 2 348 cases split that I reloaded and have not had any factory ammo split. Sounds like a possible case of brittle brass ?????

[348WCF]

Thanks for all the answers folks, I have had an almost overwhelming response on this and a couple other sites that seem to confirm a problem with the commemorative run of ammo. Best regards,
Jim