What's with the bolt on a Mosin Nagant

Straightshooter2

US Veteran
Joined
Oct 14, 2011
Messages
2,580
Reaction score
2,546
Location
South of Gritville
After firing about four rounds, it became almost impossible to work the bolt and chamber another round. The bolt would come about halfway up and stop, taking tremendous effort to eject the spent casing. By the sixth round, we could not eject at all and I had to take a plastic head hammer at home to open the bolt completelty ejecting the spent round.

Anyone know what causes this phenomena? I can't see even the Russians giving their troops rifles that would stick like that. Anyone know a solution? Just wondering since it seemed a very accurate weapon at several hundred yards.

CW
 
Register to hide this ad
You're not a Noisy Maggot owner till you keep a 2X4 in your possibles bag.
Anyone know what causes this phenomena? I can't see even the Russians giving their troops rifles that would stick like that.
Russians viewed their conscripts as cannon fodder, shoot till they run out of ammo, then clog the tank tracks with their bodies.
That and drunk Babushkas doing final assembly in glorious peoples assembly building #17

Edit to add:
You can tell a lot about what a country thinks of it's soldiers just by the selector switch positions.
Those that train and teach marksmanship skills as well as battlefield survival will have the first click go to semi auto.
Carnage and overpowering urges to sacrifice for the motherland will usually click straight to full auto.
 
Last edited:
I am pretty sure that is caused by left over cosmoline. As you fire the rifle, it heats up,eventually "melting" the cosmoline. I would think a GOOD cleaning should help. YMMV
 
Pull your bolt and check the chamber, make sure everything is clean. I have 3 and bought one for my son, no trouble with any of them. Make sure the ammo is clean and not tarnished also.
 
"Sticky Bolt" is a common complaint with mosins. They were cosmolined and in storage for years, getting the chamber properly clean often helps. Certain lots of surplus seem to stick more than others as well. I own several mosins and have only had the problem with a few of them. I used fine steel wool and solvent to clean the chambers. Dissassemble and clean the bolt as well and apply a little tetra grease on the bolt cam surfaces. The mosin is a sound and durable rifle that was in service for many years. Most often all they need is a thorough cleaning.
 
My son had one that you could barely move the bolt after a shot. I suggested he try sporting ammo instead of that military surplus steel varnish covered stuff he was shooting. Immediate fix. The brass cased stuff worked just as smooth as glass. The military surplus with the coating just plain wouldn't work.
 
"Sticky Bolt" is a common complaint with mosins. They were cosmolined and in storage for years, getting the chamber properly clean often helps. Certain lots of surplus seem to stick more than others as well. I own several mosins and have only had the problem with a few of them. I used fine steel wool and solvent to clean the chambers. Dissassemble and clean the bolt as well and apply a little tetra grease on the bolt cam surfaces. The mosin is a sound and durable rifle that was in service for many years. Most often all they need is a thorough cleaning.

This is good advise and most likely the problem. You may also check the chamber for any burrs.
 
When I bought it, it was FULL of cosmoline and I disassembled it and did a pretty thorough cleaning blasting into nooks and crannys with grease remover and cleaner. desi2358, I'll take it apart again and try that steel wool trick with the chamber. Shooting Padre, I was wondering about the casings. I remember reading that the copper cases the U.S. used in those early Springfields caused them to jam and that was why the switch to brass. That same author said many of the rifles recovered at Little Big Horn were jammed due to the copper cases. Maybe the steel cases do the same in the 91/30. Oh, btw it is Wolf ammo but still the steel cased stuff.

Edit: I just found this online. "If that happens though you might be using lacquered ammunition which after the bore heats up turns into a glue and sticks the bolt. or you have not cleaned the bore good enough."

CW
 
Last edited:
Using fine steel wool in the chamber (not the bore) is not likely to do anything except get the thin layer of hardened cosmoline out and maybe polish the chamber a little. A lot of guys on the mosin boards recommend it and I've had good luck with it myself. The russians packed these guns away for long term storage and their version of cosmoline can be hard to remove sometimes.
 
I have also used the copper cleaning pads. I have 3 Mosin Nagants. Round receiver, Hex receiver and the M44 and I have not had any problem with them. I did clean them well. One trick I do with cosmoline is put the parts in a black trash bag out in the sun. I also use carburetor cleaner from Wally World to dissolve it.

When I shoot MilSurp ammo, I use Slip2000 725 CLEANER / DEGREASER. SLiP2000™ - 725 Cleaner / Degreaser It is water based and does a great job of cleaning the bore. It works on cosmoline too.

I also found this on another forum.

TipsOfTheTradeOne
 
Mosin "sticky bolt" syndrome is most often caused by rapid fire using lacquered case ammo. After that the most likely causes are cosmoline or a chamber burr.

Is it a Soviet or Finnish Mosin? The Finns used a storage grease called sisu, and when it gets pretrified it is way worse than cosmo, especially in the bore.
 
I chuck a 20 gauge shotgun brush on a rod into a cordless drill, stick it down in the chamber and start pouring mineral spirits down it while I run the drill. I don't have any problems with sticky bolt on any of my Mosin's and all I shoot for the most part is surplus ammo. I did have a bolt on one that had some slight burrs on the locking lugs, a fine stone took care of those.
I also made one of the electronic bore cleaners to use on one particularly nasty Chinese Type 53, did a great job of removing all the cosmo and copper fouling, but also exposed the sewer pipe pitted bore with no rifling. I suggest the mineral spirits or boiling water since cosmoline melts at a relatively low temp.
 
Check the firing pin protrusion to. Many are set out way too far at .080" and sometimes more.
Aside from the chance of piercing a primer it drags on the case longer when opening the bolt as they indent much farther than needed.
It doesn't cause a great deal of extra resistance but some that's unnecessary.
The small screw head at the back of the cocking piece is for adjusting the firing pin.
.040" +/- is where most commercial rifles are set. The M/N doesn't need anything more than that w/decent ammo and correct headspace.

The laquered cased ammo is the usual problem with the rifle. It's difficult to remove from the chamber w/o using a solvent and brush. Then you shoot it some more and you're right back to the same problem again.
They must have used different types as some lots of that type of ammo don't seem to give any difficulty. It's been used in everything from the M/N to M/Gs. I think some of the AK rounds were a laq. coated steel case too. Never heard of a problem there,,but that's some modern stuff yer talkin about.

My last M/N was a Finn 39. All I ever shot in it was Bulgarian mfg stuff w/ steel cases that are copper plated . The rifle was clean and perfectly maintained,,headspace correct, ect. Even then the bolt lift would occasionally become hard at the half way point. Not always.
Poor QC ammo?,,I need to work out?,,aliens?? the 1897 M/N action it was built on was giving it up??
Who knows. It's in a better place now.
 
My smith says a sticky bolt, especially as the barrel heats up, is usually attributable to a head-spacing problem. Many of the bolts and receivers were mismatched during the hasty refurb process at Russian arsenals and tolerances started to get sloppy. We're talking thousandths of an inch here. If off substantially, you likely have to re-ream the chamber at the least.
 
I chuck a 20 gauge shotgun brush on a rod into a cordless drill, stick it down in the chamber and start pouring mineral spirits down it while I run the drill. I don't have any problems with sticky bolt on any of my Mosin's and all I shoot for the most part is surplus ammo. I did have a bolt on one that had some slight burrs on the locking lugs, a fine stone took care of those.
I also made one of the electronic bore cleaners to use on one particularly nasty Chinese Type 53, did a great job of removing all the cosmo and copper fouling, but also exposed the sewer pipe pitted bore with no rifling. I suggest the mineral spirits or boiling water since cosmoline melts at a relatively low temp.

This, take a 20 ga. mop full of thinner, Hoppes, whatever and put it on a drill, let it run in the chamber for a while then take a 20 ga. brush and do the same. This and about 100 rounds has the once somewhat sticky bolt on my 36 Tula hex smooth. Not Mauser quality but far better than when I started.
 
I don't have any issues with mine but my son-in-law had some with his. I tried cleaning and polishing but it didn't help. His was sometimes difficult to even close sometimes. He bought a replacement part at the front of the bolt for about $15 or so and no more problem.
 
Two freinds and I had Finnish models. We took a section of plastic drain pipe capped an end filled with deisel dunked in the metal parts and let set for a week wiped and swabbed let dry all was ok.
 

Latest posts

Back
Top