Flawed Mosin 91/30

Hey Folks - first post

I recently bought a 1943 Mosin-Nagant (Iz) that has an odd (to me anyway) problem.

As best I can tell, the breech has a shallow quarter-inch wide void in the metal casting about a half-inch inside the chamber. It's about an eighth of an inch deep.

The round goes in smoothly, but once it is fired the case expands into the void, jamming the round from being extracted. At first it was so bad that I had to kick the bolt up and stomp down on it with my foot to eject the round. Once I figured out what was happening, I tried to smooth the area inside the chamber and I improved the behavior some. It is now possible (but uncomfortable) to eject the round normally with your hand on the bolt.

If there was a way I could fill this void so that the shell casing was not pressed into it, I would solve the problem. The gun shoots fine, otherwise.

I don’t have the facilities to try to spot weld a tiny patch within the chamber, then re-mill it cylindrical. It’s also not cost effective to pay a gun smith to do that, either. I’m stuck with patching it somehow myself, or just hanging the rifle on the wall as a decoration. Not to worry, I have another Mosin (’37 Tula) which is perfect.

Any ideas? Liquid metal, epoxy, silver solder? Followed by honing the cylinder (flap-sanding with a long shaft). It doesn’t need strength (except for compression) but must “stick” to the steel inside the shell bore.

I say I can’t weld it, but I might be able to jury-rig some means of arc welding a spot in there. Maybe with a brazing rod and a car battery? What do you think?

I think this flaw has been in the rifle since it was made - looks to me like a void in the original steel blank. Don't think it's corrosion or damage from a faulty casing. Have any of you ever run into a problem like this? It is common for wartime Mosins? I know towards the end, the Reds were suffering materials problems and were cutting quality control to keep the arms flowing.

Just curious if anybody has run into this before.

sbucy
'37 Mosin-Nagant
'43 Mosin-Nagant
'48 Lee-Enfield
?? Chinese SKS
1870/87/15 Vetterli-Vitali, 6.5mm Carcano

Could be an ex-sniper rifle that they didn't fill the screw holes properly creating the void.

Are you having trouble with both steel and brass cased rounds? If only brass, using steel cases might be a temporary solution.

Yup - problem with both. In fact, the thin steel cases are worse, I think. I got some relief by flap sanding/polishing the entrance of the breech down to the defect. That definitely helped. I could try to take off another thousandth I suppose. But it's really hard to get tat it - have to make a flap sander from a long dowel and work the hand drill in from the rear after taking out the bolt.