The Russian Mosin Nagant Forum

I have several Mosin Nagants at this time.
1936 91/30 Finnish Capture
1955 T53
1915 New England Westinghouse Finnish Capture

The 91/30 and T53 are not picky which ammunition I place in them. The N.E.W. M91 is very picky. I have surplus ammo marked with a "82" and also some PPU ammo that I have been reloading. The PPU ammo will not load into the M91. Please see the jpeg attached for ammo dimensions. It seems the only difference is the two length dimensions where the case necks down. What is the best way to solve this?
A) Only shoot surplus ammo? (I really like loading my own)
B) Is there a different brand ammo or brass that I can buy that will have the same dimensions as the surplus ammo?
Any suggestions would be greatly appreciated.

Will the PPU brass chamber after you have resized it?
You might try Lapua brass, but it is PRICEY.

I used some winchester white box in a M91. It was a 40 finn though. Have some Prvi but haven't tried it yet. There is also sellier & bellot.

I tried to chamber the resized and trimmed PPU brass and no luck. I will check out the alternatives.

I don't understand the problem, but I do not have a M91 for reference. I have been reloading PPU brass with great success in the M91/30. I can't imagine what the difference would be unless you did not trim your PPU brass after firing or your chamber dimensions are different from standard. I trim the brass to make sure it does not exceed the trim length as specified in the Hornady manual and I have had no problem with any of my guns. In fact the PPU reloaded rounds load easier than any of the steel case surplus. I suspect this could be a problem with your brass exceeding the overall maximum case length. This is a dangerous situation as forcing the rounds to chamber can cause unusual pressures. Get yourself a caliper type measure (I use a RCBS tool) and make sure the case lengths are to specifactions, then go from there.

Do you full length resize?

Did the original factory loaded PPU work in the M91?

Have you tried to keep the brass sorted and only put the reloaded ones into the same rifle that originally fired the cases?

I understand that would be optimum performance to keep them in the same rifle, but man that would be a chore. I have at least 5 mosins

desdem12 wrote:I understand that would be optimum performance to keep them in the same rifle, but man that would be a chore. I have at least 5 mosins

Well he would not have to do it for all of them since the others seem to work ok, just for the picky one.

Well that be true but i was a pre wondering of my own problems

Thanks everyone for posting. I have four mosins and these PPU brass shoot fine in all but the N.E.W. M91. I have tried two different surplus ammo and they shoot just fine in the M91. I posted the differences in the dimensions in my first post on this. The length dimensions related to the neck of the case have to be causing a headspace issue. I have ordred 00 S&B cases and hopefully they will load without problem.

thecoltsman wrote:Thanks everyone for posting. I have four mosins and these PPU brass shoot fine in all but the N.E.W. M91. I have tried two different surplus ammo and they shoot just fine in the M91. I posted the differences in the dimensions in my first post on this. The length dimensions related to the neck of the case have to be causing a headspace issue. I have ordred 00 S&B cases and hopefully they will load without problem.

I trim my cases to that specified in the 8th edition Hornady reloading manual. That manual states the maximum case length as 2.115" and the trim length as 2.105". This has to be a problem with case length and maybe a chamber on the M91 that is a little shorter than standard. I feel certain that you can correct this by trimming the cases to spec and making sure that your cartridge overall length with a seated bullet does not exceed that specified in the manual. My manual says that max C.O.L. for the 7.62x54r is 3.048".

Thanks, I have trimmed my cases to 2.108". They still will not fit. This is the same trim length as the surplus ammo. Can everyone read the entire picture above. It looked to me last night that some dimensions got cut off the picture.

What does "will not load into" mean specifically?

Not at all or parcially?

I'm no expert at all on these, but the amount of shell spanning between the 'I' mark, which is the same on both, to the 'B' mark, which is smaller on the surplus, will have a different angle then the brass.

/\ that angle would be less on the surplus then the brass. This angle, if not matching the rifle chamber, will not allow the round to seat.

Will the round go in at all? Maybe most of the way and stop with about .5 to fully chamber?

Then again, i have NO clue what i'm talking about.. lol.. just some quick figuring.

Full length resizing doesn't return the cases to original factory dimensions. Close, but not quite. Could be your dies are a little on the loose side, or the chamber of your M91 could be a little tight or a combination. If the later, you may need to invest in a set of small base dies to size the cases a little smaller.

When I say the cases will not load, I mean that I can put the case in the M91 and the bolt will get nearly closed. Much like the No-Go gauge. I can only assume that the N.E.W. Gun has a much tighter fit in the breech. I am using a new set of LEE 7.62x54r dies. Only ran about a hundred cases through them so far. I may have to invest in the other die set as MosinJohn suggests.

thecoltsman wrote:When I say the cases will not load, I mean that I can put the case in the M91 and the bolt will get nearly closed. Much like the No-Go gauge. I can only assume that the N.E.W. Gun has a much tighter fit in the breech. I am using a new set of LEE 7.62x54r dies. Only ran about a hundred cases through them so far. I may have to invest in the other die set as MosinJohn suggests.

Come to think about it, I think I have tried rechambering empty cases and these guns and they just won't do it. Unlike my Ruger M77 that will chamber unloaded .30-06 cases all day, I can't get the Mosin Nagant to chamber an empty case, either sized or not sized. I suggest loading one dummy round with no powder or primer and try to chamber the round. Make sure the trim specs and C.O.L on the loaded dummy round are by the book.