Bad chamber in mosin?

[CL4P-TP]

posting here because Im wondering if this would affect my ability to ever handload for this rifle. Anyways the rifle cycles well with steel cased surplus and mfs stuff from 150 to 203 grain. But last time I was out I shot some brass cased PPU through it and noticed it was much harder to extract than the steel cased stuff. I noticed that the case walls seemed hazy after firing, this doesn't occur in my old p17 308 target rifle with federal brass. I don't know if the haze is from expanding in a loose chamber or simply from chamber texture. Also I noticed 3 rings just beneath the shoulder that went approximately 80% around the case. I read a hornady reloading manual but still don't know what this means for sure. I don't know what this means for me or the future of this rifle so any insights would be appreciated.

The rings are hard to see but can just barely catch a fingernail.

 

[wce323078]

I would be taking a paper clip and make a little hook and feeling inside case. but looking at that case maybe hooped. and I would think rifle has a generous chamber Which like a lot of military rifles to allow for crud ETC. and still function. Most of these type of firearm are not designed for the cases to be reloaded. Lee-Enfield prime example.

If you have something to cut it open and show a picture there a lot of knowledgeable people on here

 

[bigedp51]

I'm thinking Ivan or someone rechambered this rifle because the shoulder has moved way forward.

Stand the cases up on their base and take another photo. It looks like Ivan read P.O. Ackley's book on improved cartridges and reamed the chamber.

 

[bigedp51]

Also your Photo Bucket account is not set on private and I could look at all your photos.

 

[Hitzy]

I would be taking a paper clip and make a little hook and feeling inside case. but looking at that case maybe hooped. and I would think rifle has a generous chamber Which like a lot of military rifles to allow for crud ETC. and still function. Most of these type of firearm are not designed for the cases to be reloaded. Lee-Enfield prime example.

If you have something to cut it open and show a picture there a lot of knowledgeable people on here

Well if you know how to reload, a field gauge swallowing chamber isn't much of a concern. That's what neck sizing is for.

 

[bigedp51]

I would be taking a paper clip and make a little hook and feeling inside case. but looking at that case maybe hooped. and I would think rifle has a generous chamber Which like a lot of military rifles to allow for crud ETC. and still function. Most of these type of firearm are not designed for the cases to be reloaded. Lee-Enfield prime example.

If you have something to cut it open and show a picture there a lot of knowledgeable people on here

All military chambers are larger in diameter and longer in headspace settings than commercial SAAMI chambers. The reason why the Enfield doesn't like being full length resized is because our American SAAMI dies are on the small side. "AND" American made .303 British cases have thin rims and wimpy thin cases that do not like being fired in long fat British chambers.

If you want to shoot and reload your Enfield rifle then buy Prvi Partizan brass. The Prvi Partizan case and the HXP case below were both fired in the same Enfield rifle. The Prvi case below has thicker rims, a larger base diameter, and .010 thicker case walls in the base than any other modern .303 case made.
(the prvi brass is made Ford Truck Tough)

 

[kawicrash]

Still better than most Enfield chambers.
Maybe the o-ring trick would be helpful. Get a small o-ring and slide it down to the rim. This centres the case in the chamber and also takes up any excess headspace. Helps extend case life in .303 Enfields.

 

[CL4P-TP]

Next time Im near the cases I will get some more pictures. Im out for the next two weeks. But I can zip one in half and take some more pictures. Shoulder is blown out a fair amount, Ill try to take a measurement from the rim and see how much its moved.

 

[CL4P-TP]

Ive never heard of the o ring trick before. sounds interesting. I may have to try it with dummy rounds but I feel like there would be extractor issues. This rifle is a 1942 and it is the prime example of a bad mosin. I think it had every possible issue. Thankfully the others that came with it were a hex and an ex sniper.

Thanks bigedp51 for the headsup on that.

I originally intended to see how much I could polish this turd. I was curious if I could handload or even load cast bullets for the oversize .303/.314 bore. But if there is a chamber defect that will prevent that it would seem that Ive reached the peak of this dungs luster. At any rate I will try to get more details on the fired case to see how much it is actually deforming.

Also the brass I used is privi/PPU(I belive they are the same) so I believe its decent quality brass.

 

[bigedp51]

I was taught the rubber o-ring trick in another Enfield forum by a Canadian with the screen name of TerryinVictoria years ago. And it will work with any rimed case and is very simple to do.

So here goes.

Below is what happens when you fire a thin wimpy commercial .303 case in a military Enfield chamber.

Below you slip a thin rubber o-ring around the case and it holds the case against the bolt face and the case can not stretch.

Thereafter you neck size only and let the case headspace on its shoulder and not the rim. A .303 British case forming and trim die can be used as a shoulder bump die and the die will not touch the body of the case.

Normally I fire form a lot of cases at once so I use .312 pistol bullets and reduced loads with Trail Boss powder to make the brass butt plate softer.

 

[CL4P-TP]

Well I was able to get a hold of my brass and cut a case open.



To my untrained eye is seems that there are no major safety issues. Just a rough cut chamber around the shoulder area maybe? Could this be whats causing the more difficult bolt lift?

Bigedp51 thank you for the explanation it was very easy to understand and it is greatly appreciated.

 

[donor]

I almost bought 1942 stamped 91/30 with really bad (rough) machining marks all over it.It also had badly machined chamber-I could see rings much like those when bore light was shining into it.
Seller never reloaded but was swearing it shoots steel cases perfectly fine and is "minute of nazi" accurate.We couldn't agree on price

Technically rough machining like that shouldn't matter if steel cased ammo is shot.Steel case is't playable enough to even notice that.
Reload like 303 like guys above suggest and it will be cool.

 

[fiddler]

Bad chamber in mosin?


I reload for 7.62.54r for several years, and I have had many Mosins, M44s, and M38s that all reload fine without damaging good brass.


I would examine the chamber more closely, and I would also measure your cartridge length before and after you fire it. If you have irregular headspacing the shoulder and neck measurements will be too long when measured from the base of the case.

 

[Hitzy]

Bad chamber in mosinj


I reload for 7.62.54r for several years, and I have had many Mosins, M44s, and M38s that all reload fine without damaging good brass.


I would examine the chamber more closely, and I would also measure your cartridge length before and after you fire it. If you have irregular headspacing the shoulder and neck measurements will be too long when measured from the base of the case.

The cartridge has a rim, headspace is measured on the rim, not the shoulder.

 

[kawicrash]

Wouldn't worry me a bit. Just consider it a 54R Improved.
Neck size or carefully full-length size so as not to push the shoulder back, it will now headspace on the shoulder and case life should be fine, especially if you fire form with an o-ring.
( I find ponytail or loom elastics doubled work great too, especially if your headpace at the rim isn't too bad. Just don't let anybody see you using your daughter's pink elastics.)

 

[bigedp51]

To my untrained eye is seems that there are no major safety issues. Just a rough cut chamber around the shoulder area maybe? Could this be whats causing the more difficult bolt lift?

Many wartime produced Mosins were quickly and sometimes crudely made in a rush to get them to the troops. The first lifting of the bolt is primary extraction and this is to break the case free of the chamber walls. Two things can cause hard bolt lift, bolt timing or the case sticking to the chamber walls. Scrub the chamber with a chamber brush and then polish with a shotgun cleaning mop with J&B bore paste and Kriol. The coating on some steel case ammo can transfer to the chamber walls and cause the brass case to stick to the chamber.

If you decide to shoot and reload brass case ammunition check the headspace to minimize case stretching.

I use a RCBS case mastering gauge to check for stretching and thinning in the base web area of the case. Excessive headspace and the chambers rough walls will increase case stretching.