ruptured casings on my mosin

[zeaken]

I bought a case of surplus russian ammo. it came in a grayish sardine metal can that was so old it was turning white and gaining texture on the outside. the ammo on the inside seems fine but the little papers the 10rd packs are wrapped in nearly fall apart from the touch. i have no idea but something in my mind tells me this was a WW2 surplus. i bought the case a while ago so not sure.

I was shooting my mosin yesterday and upon ejecting one of the casings i noticed it ruptured. this is actually the second casing in this batch to do this, both did it the exact same way. they ruptured just below the neck of the casing vertically (along the long side) about 1cm long. one of the ruptures ripped quite wide this most recent one was like a paper cut.

I would assume this is not safe and i probably should not use this ammo any more is this correct? i have also found 3 cracked necks so far in this can as well so i am beginning to suspect its bad brass but i would rather lose 200 rounds and be out some money then have a gun blow up in my face and maim me or worse.

 

[clark500]

In my less than expert opinion...

Neck splits after firing are not uncommon and are not dangerous. Notice I say NECK splits.

I would discard any rounds that are split before firing.

However, if you see anything that looks like the picture below I would discontinue use.

If I am off base, somebody please correct me.

 

[leadcounsel]

Mine do it too.... I'm not concerned. The entire round is cased within the barrel and bolt.

 

[rcmodel]

As clark500 noted, case neck cracks are not a safety issue.

Cracks further back can be, if they get close to the case head.

Those shown in his photo would blow hot gas into the action and could wreck both the gun and the shooter.

Once high-pressure gas escapes into the bolt & action you have a very dangerous situation.

rc

 

[Slamfire]

Pull a bullet or two and see if there is green corrosion in the case or on the bullet.

When powder deteriorates it outgases nitric acid gas. New powder has stabliziers that sop that stuff up, but there is only so much stablizier in the powder. The Army scraps double based powders at 20 years, single based at 45 years.

If your powder is outgassing nitric acid gas it will cause case neck cracks. Case necks are thin and highly stressed. If you find that corrosion due to nitric acid gas you will need to dump the ammunition. In time that acid gas will cause splits in the thicker case sections and if you get a ruptured case head, we will be able to substitute your Nagant for this Swede M96.

 

[Riss]

I would love to hear the story on that one ! Looks nasty. I hope the shooter made out better than the gun, because the gun is done for.

 

[zeaken]

the cracks are the style you posted in that picture but they didnt form at the base they were right below where the bullet shapes inward to direct pressure ie about in the middle of the casing. i will take one apart and see if there is this corrosion you speak of inside. one of the rounds.

i will try and get a picture up as well as i saved one of the casings which had this problem

 

[zeaken]

on the back of the casing it says 3, 10, 52 with the russian star on the top. does this mean it was made 3/10/52?

 

[Slamfire]

That is a body split.

If this was a new case I would just say it was a random brass flaw.

But this is 1952 brass.

See any corrosion inside an unfired case?

I would love to hear the story on that one ! Looks nasty. I hope the shooter made out better than the gun, because the gun is done for.

I saved the picture, forgot I had it till recently, and have no idea of the story behind the accident.

But the blood says a lot about what happened to the shooter.

 

[Cosmoline]

That's Bulgarian ball ammo. Are the bullets yellow tip heavy? If so note this:

Although some lots have problems with split necks and show signs of poor storage conditions, this ammunition is reasonably accurate and reliable.

http://7.62x54r.net/MosinID/MosinAmmo016.htm

Google the Bulgarian and you'll see a lot of similar reports.

Personally I'd set it aside and only use it with a Mosin that doesn't have this problem with it. There are a lot of variations in chamber dimensions between Mosins. Whichever rifle you're shooting may have a chamber a little broader than the Bulgarians anticipated.

 

[zeaken]

here is a picture of a casing i cut in half. there is green in random parts but its not a solid coating as you can kinda tell from the picture. is this a fatal amount of corrosion?

 

[Cosmoline]

I wouldn't think so--it looks more like a patina. Have you tried these in a different Mosin?

 

[Maj Dad]

I used to get the same cracks in surplus 7x57 and other old stuff. Never hurt anything and never affected the web/head areas. Just old & brittle and split versus expanding with the pressure of firing.
(Some of the 7mm was 1912 vintage!!)

 

[Slamfire]

Your powder is outgassing nitric acid. It is past its shelf life. Case necks are usually the first thing to split as they are thin and highly stressed.

Your call. If you continue to experience body splits on a regular basis, pull the bullets, take the brass to the salvage yard, and pour the powder out on the lawn.

If you plan to keep the ammunition, store it in a cool and dry place. The cooler and drier the better.

Powder aging accelerates with temperature.

 

[navyretired 1]

These look just like inbrittlement of brass cases which I've periodically gotten from surplus ammo for 40 years.
If I was getting one in ten rounds I wouldn't use but one every 40-50 rounds is almost what I get from my 3X reloads and I've nevery known it happened till cleaning and inspecting after shooting.
I keep a close lookout for case head seperation when inspecting and don't take a chance but neck and shoulder splits are very common and IMHO not extreme

 

[zeaken]

this is probably the second round to do this out of 100 rounds. I am going to go through the rest of the box and toss anything with dings, neck splits or anything that looks less then perfect.

since this seems to be an issue with pressure....now i dont know a lot about ammo but couldnt i just remove the bullets on uncracked casings to relieve the pressure and then reattach them? or is it an issue where once under pressure thats the end of things?

 

[rcmodel]

No.
It doesn't work that way.

The case necks are age hardened, and/or corroded, and pulling the bullets & reseating them will not change that at all.
It would just work harden the brass further and make it even more likely to crack.

The only way to soften the brass is to anneal it by heating it red hot and quenching in water.

To do that you would have to start out with empty unprimed cases.

In short, it is what it is.
Shoot it, or not.
It's up to you to decide.

rc