View Full Version : Moisin Nagant question

January 18, 2012, 07:59 PM
I bought some surplus ammo, think it was Polish sold some of that to a friend his son and a friend of sons went and shot some both Mosins ended up with casing stuck in rifle the day they shot the ammo, he had to pull very hard to get bolt to eject shell any idea why both would have same problem? one gun was his the other was his sons friends gun he also said he put another of the same surplus ammo in his gun after he got the casing out and the bolt had no problem tossing the shell out.

January 18, 2012, 08:27 PM
possible cosmoline still in the chamber?

January 18, 2012, 08:36 PM
Yeah, I was giong over that in my noggin. All I could come up with was possibly a dirty chamber, old laquer buildup, carbon, etc- add that to old ammo with an unknown history of how well it was handled, manufactured, stored, shipped. We're not even sure if it was ammo intended for a rifle or a machinegun (light ball vs heavy ball). Could be a lot of possibilities and/or variables there. Also, is anyone even sure of the condition of the specs of the chambers?

DE Shooter
January 18, 2012, 10:26 PM
I had some Polish heavy ball in laquered steel. It would stick badly after the barrel heated up. Very hot stuff, a kicker out of a M44. I won't be buying anymore.

January 21, 2012, 12:15 AM
I'm going to agree with DE on this.

I have the same problem with my Moisin, if I put 30+ rounds through it in an afternoon and forget to eject one right away, it is a pain to open.

Just make sure you clean it good afterwards.

January 21, 2012, 12:32 AM
Is the light ball ammunition intended for the bolt action rifles? Would interchanging the two cause cycling problems?

January 21, 2012, 12:55 AM
With every Mosin I buy, my trick to getting the chambers free of cosmoline is to chuck a cleaning rod into the cordless drill and buzz the chamber with a 28 gauge brush and mineral spirits. My old 1940 91/30 was tough to open some times until I learned that trick and now she's a VERY smooth rifle.

January 21, 2012, 01:24 AM
I had the same problem but i fixed it a different way. the end of the extractor had a burr on it, sometimes the extractor would go behind the shell leaving me to push it out with the cleaning rod. a little emry cloth and now it's silk.

January 21, 2012, 11:02 AM
I had some Polish heavy ball in laquered steel. It would stick badly after the barrel heated up. Very hot stuff, a kicker out of a M44. I won't be buying anymore.

+ 1.

It's the ammo. I've got some steel case surplus that can be very hard to eject out of my Mosin as well.

January 21, 2012, 11:46 AM

This is the box lid from a 1944 Finnish repack of 1930's vintage Russian yellow tip heavy ball. By the people who actually used this cartridge in an official capacity.
The "D" on the box is the same "D" you see on the barrels of Finnish Mosins and the "7.62 kiv. patr." translates into English as "7.62 rifle ammunition".

That ought to answer this question: "Is the light ball ammunition intended for the bolt action rifles?"

January 21, 2012, 12:10 PM
I've seen pitted chambers cause the stick-bolt-syndrome on Mosins before.

Usually it is just a dirty chamber though, and there are guides online on how to clean/polish your chamber.

January 21, 2012, 03:47 PM
what i did to fix my sticky bolt issue was first make sure all the cosmoline is out of the rifle, especially in the chamber, which 99% of the time is what causes the sticky bolt. Then go get yourself a 12 gauge brush(correct me if im wrong, im not at home and i don't remember exactly what size shotgun brush i used, will update tonight when i know for sure) which fits perfect in the chamber for cleaning. Put it in a drill and run it in the chamber for like 30 sec to a minute with some cleaning or gun polishing compound. I forget the exact name of it, but i went to a local gun shop and they let me borrow some.

Just don't go crazy with the drill or really fast, just take it nice and slow. After using the brush, get a rag and clean out any compound or whatever you used and try it. If it still sticks, do it alittle more. It only took one time to get my fixed, but every rifle is different depending how much crud is caked in there. That will fix your problem!

Also, i forgot to mention, stay away from brass cased ammo that comes in those packs wrapped with paper and a rope unless it came in a spam can and your the one that opened it. I have found that those cases are usually pretty crappy from sitting so long without any protection with those thin papers wrapped around it. I bought a couple packs of it when i bought my gun and the cases expanded so much everytime, they got stuck or cracked. I switched to a different ammo and worked fine. Try using the brush to polish your chamber first, and stay away from that ammo and you'll be set

May 17, 2012, 10:12 AM
I bought both Russian and Bulgarian surplus, and both were copper washed cases. Its a very good possibility the Polish stuff is laquered, which will melt off the case and cement it in the camber.

May 17, 2012, 12:06 PM
I know a guy who fires lacquered ammo in a machine gun. No issue

Not likely to be the lacquer as a problem though a cruddy chamber is a good possibility.

May 17, 2012, 11:23 PM
MN's are a bit crude. By that, I mean that the machine work is usually rough. Sticking ammo in them is usually the result of cosmoline still in the chamber or that the chamber is rough. 20ga. brush with turpentine attached to a hand drill will clean out the cosmoline. I also recommend that you polish the chamber too. There are several ways of doing this and you can see some of them on youtube.

Ive never had a problem firing any of the surplus ammo once cleaning and polishing has been done.

May 18, 2012, 12:11 AM
I’ve never seen a MosNag that had a roughly machined chamber. Seen many with whatever cosmoline-like gunk they used … dried and coating the chamber like car wax. It can look squeaky clean in there, but ...

A coated chamber will often cause a steel case to stick after firing. Oddly enough, brass cases rarely stick even when the chamber is coated really bad. Thic caused a lot of legend about tight chambers, bad steel cases designed for other guns, lacquer gluing them in, etc. What happens is that the heat melts the goo and it becomes glue … If it happens, DON’T try to force it open, unless you want to learn the hard way about the bolt and extractor. Lay it aside and let it cool. As it cools, the goo turns loose of the case (almost every time).

If you notice any stiffness in the bolt after firing, clean the unholy you-know-what out of the chamber. It should be able to digest any steel ammo just fine. It isn’t a quick chamber brush thing either … that stuff can be amazingly tough to get out.

May 29, 2012, 10:05 AM
Mabey the reason your friend fired a MG with laquered ammo and had no problem was because of the much higher cyclic rate of a MG compared to a bolt action. Mabey the cases didnt have time to stick? Never fired a MG, so dont know for sure.

Mr Budha
May 29, 2012, 02:25 PM
I just recently bought and shot a 1933 Mosin. The first few shots were really tough to get the bolt back open also (Shooting new, non-corrosive ammo from aim surpuls). It got better the more I shot but the bolt does like to be finicky sometimes. Just put some muscle into it ;)

May 30, 2012, 10:39 AM
I was told by an Insensitive Munitions expert that the design shelf life of ammunition is 45 years for single based and 20 years for double based.

Anyone who thinks gunpowder will last forever is fooling themselves.

Section from




Nitrocellulose-base propellants are essentially unstable materials
that decompose on aging with the evolution of oxides of nitrogen. The
decomposition is autocatalytic and can lead to failure of the ammunition
or disastrous explosions. Many substances have been used to stabilize
nitrocellulose-base propellants, but by far the most widely used substance
is diphenylamine (DPA).

The use of diphenylamine to suppress the autocatalytic decomposition of nitrocellulose contained in propellants was apparently first proposed by Nobel in a German patent in 1889 (48). Shortly afterwards, Germany in great secrecy adopted the use of diphenylamine for most propellants. However, other countries soon were using diphenylamine for this purpose and by about 1910 its use was fairly universal.

Anyway, one of the issues with old gunpowder, besides autocatalytic explosions, is burn rate instability. As the powder ages the grain of the powder changes. Double based powders the surface become rich in nitogylcerine even though the energy content of the grain decreases over time. Either or these, both of these, or a combination of these can create pressure spikes.

This has and will blow up rifles.

May 30, 2012, 11:49 PM
I don't know about polish but I have heard of bulgarian surplus sticking. just tighter fit in the chamber and hotter loads. it's a problem to be sure but sometimes that's the price we pay for shooting cheap. some rifles have loose enough chamber tolerances to handle these smaller comblok ammo batchs but some have to have good old tula.

I was told by an Insensitive Munitions expert that the design shelf life of ammunition is 45 years for single based and 20 years for double based.

Anyone who thinks gunpowder will last forever is fooling themselves.

2 years ago I cracked open a spam can of 45ACP ammo that was packaged in 1943 and have yet to have a failure with it out of either of my 45s. ammo does degrade over time but depending on how it was stored I will guaranty that it will last at least 67 years.