How To Episode 8: Mosin Tight Bolt Fix 

My Mosin has had this problem since day one, a gunsmith couldn't figure it out. I'll give your fix a try and if it works you can add it to the list of beers I owe you.

Gents: My bolt face edges were peened over and the extractor was VERY tight and the face of the extractor needed a polish. I cleaned up the peened over edges, bend back the extractor a bit, and polished the extractor face with a high speed rotory tool and polishing compound. Chambers like a dream now! Thanks to this video I became aware of these issues and how to fix them easily. Thanks a million for making this video.

This is the exact problem I'm having with my Mosin, and it's the biggest one for me. Thanks for making this video Erik, and showing how to fix it in such an easy way. Can't wait to take it to the range now that I don't have to slap my bolt shut every time I want to chamber a round.

Hey Eric, just wanted to say THANK YOU for this video... It worked perfectly on my Sako M-39. No more slapping the bolt, I'm so happy!

this helped a lot. i had the reverse problem, bolt sticking closed when hot/fired. my ejector was bent in & slightly twisted so it couldnt sit evenly. i held the ejector back with a small nail & used a dremel to carefully put a slightly open bevel in the bolt rim & under the ejector, bent the ejector back as close to perfect as possible & now it cycles rounds much better. still not as smooth as yours, but a lot closer than it was. hopefully it performs just as well hot. Thanks again Eric.

Thank you so much for putting up all of these Mosin videos over the years. Your tips and knowledge have helped me improve the function of my Mosin and in turn the enjoyment I get out of shooting my rifle. These videos never get old and I always learn something new! Happy New Year!! Thanks again!!

My M39 is the smoothest rifle I own and the trigger is fantastic. The quality of mosins can vary like day and night. Great video.

you're the man, watched all your videos to help square away my mosin. I'm still having trouble closing the bolt on a loaded chamber, im going to try your fix and see if it works. thanks.

Simple fix. Never thought about that being a problem. Thanks much! You are the freaking Mosin Whisperer. Please keep them coming!

Buying my first Mosin was what got me into gun repair as well! Now I work on All of my friends and family members firearms! I'm hooked on it.

Awesome video, I just bought my first one ( 1953 Polish Mosin Nagant M44) in excellent condition. These along with the 91/30 are great rifles. I follow your videos for great information. Thank you

I evidently got very lucky on my Mosin purchase. I've got a 1924 Hex receiver, ex dragoon. It has a very, very smooth action. Great vid brother.

I have been a subscriber to your channel for a couple of years. Love your videos. This past week, I have been checking out your how-to videos. This is good stuff! I had a 91/30 a few years ago and it was a problem child of a rifle. I would have been more patient with it but, I had a sporterized gewehr 98 along with some other rifles that were more fun to shoot. Now, I am willing to give the old Mosin another chance with these how-to videos as my guide. Please, keep making these.

i have this problem frequently in mine, I was so certain it was the extractor. I reprofiled and tweaked and polished at it with little success. I never even thought to look at the bolt face. thank you, great video!

hey eric, heres a simple tip i do to smooth out my friends mosins, instead use a fine wire wheel on a bench grinder over all surfaces. then take a bore brush with a power drill and cleaning rod and insert it into the chamber and run it for about 30 seconds. that will take the burrs out of the locking lugs. lube the bolt with grease instead of oil. you can finish the bolt up with steel wool. try it. it takes minutes

Man! Thank you Eric, now all of the issues I've had with mine you have made videos on how to fix hahaha. I cant thank you enough brother. You've been a great help & teacher. Everything I've learned how to do on my moysin has been from you, from glassing, making the bolt smoother, & now this. Thanks again brother. Much love & respect

YT gun channels have come a long way..its a good thing.

If it was not for your video, would have never got a mosin. I learned a lot from you and thank you.

The finn mosin's are the best i got a 1935 M28 and it works like butter all my 91/30 needed some loving.

Mine did that too, after I left it in a humid garage (long story) for 3 days. the lands of the barrel did were orange with rust... those were a piece of cake to clean but i didn't think the chamber had done so too, until i went to the range. my casings did the same thing. I eventually got a .44 bore brush and a short brass rod, sprayed shit tons of Rem Oil in, and went to town for probably 5 minutes. i didn't have any problems after that. the bolt opens a lot easier now, too.

this couldnt come at any better time, just picked up a mosin and im working on cleaning it now. love the videos guys, especially the How To videos. keep em comming plz and thank you

Thanks man i am in the market for my first gun and really want a mosin. Your vids have really made me a fan of the rifle and I can't wait to own one my self

There are numerous "fixes" posted on RU-vid for this Nagant-bolt problem, and Mike, your fix has merit for sure. But, it is not the only reason for this problem. Assuming that the head spacing is correct, the bolt face being mushed or marred can obviously cause a poor seating of the ammo's ring, and thus the "sticking"! Having a perfectly clean chamber is also something that must be assured... or that alone can cause a poor seating for the round into the chamber. But, there is one more problem that many have missed... But, I discovered that the actual DIAMETER of the base-rim of the ammo can also be clearly a problem! I have two Mosin Nagants, one brand-new unissued, and another that was beautifully re-arsenal-ed, all numbers matching. Some Russian "hunting ammo -- soft pointed would always "stick", while other original military surplus ammo did not! Putting a micrometer to work brought the problem to light. The rim-base on some soft-point ammo was SLIGHTLY LARGER, than the original ammo and thus would not seat easily and would literally "be jammed" into proper battery. Cleaning the chamber thoroughly, using proper dimensional ammo, and also checking the bolt-face flange all need to be looked at. If they are all correct, the "Sticking" Nagant problem will be gone

Bending my extractor out a bit helped.

Thanks a bunch. I have several Nagants. Out of five 3 had this problem. Not anymore. Thanks again.

I have been waiting for this exact video! Polishing my extractor did half the job but I'm still not satisfied with my newly acquired T53 (or even my 91-30 after seeing your video). Just trying to snap rounds into the bolt face by hand has always felt too tight and now this explains why! I got the day off tomorrow and now a new project

Yes. I have that slap issue on one of my mosins. I'll have to try this tip. Thanks Eric.

Excellent vidieo..so Mosins brought more good stuff into our lives, your video's and inexpensive firearm fun. Thankyou for this info....my favorite series of video's are your Mosin building ones.

Thank you Eric! I've been all over the forum boards and even took my Mosin to the gun shop, but with no avail. I'm going to work on my Mosin tomorrow and hope this works.

Those are usually bought at wood crafting supply shops Woodcraft. and Hobby stores. Those files also go by the name of rafflers. But look at hobby stores, and Woodcraft shops. Hope this helps

I got into gunsmithing the same way... Bought a mosin, improved it, started doing the mosin tune ups for friends and eventually i applied to school for it.

I have a M9130 from the tula arsenal that has always ran perfectly but I am in the market for more rifles of different variants and I thank you for this informative video

I've used a lot of stuff getting the cosmoline out of the chamber and barrel. Froglube does a fantastic job. It's the only thing that I used that quickly ran clean patches with.

Thank you for the Mosin Nagant videos i just got my Mosin yesterday and have been watching your videos for awhile now and all of these help :) Thanks again

I've found that rounding or smoothing the sharp inside edges of the entire rim does the trick. The original edge is a very sharp 90 degree machined angle which, IMHO, serves no function and was only left that way to save in production time and costs. Rounding the edges allows the shell casing to slip into the head with little resistance and removes the sharp edges that may eventually fold over thereby causing the problem you're addressing with this vid.

when I was getting the cosmoline out of my SKS bolt, I made up a highly concentrated solution of boiling water and Simple Green. The grease bubbled out, and just floated to the surface, I was able to get the rest out with a few Q-tips. You might try plugging the barrel and using something similar.

I watch every video you guys do, and I am chewing my nails of waiting on the two stage Mosin Nagant trigger you said you would do several videos back... Would really love to see that. I have been buying Mosins and such to learn smithing. Thanks again.

Have a chicom 53. Works great!

Thank you for the fast reply. I do have a Mosin 91/30 with the "MO" stamped on it. 1943 Russia's Ministry of Defense. Where I live their are Fleet Farms selling them for $129.99. $10 bucks more? Thanks for the heads up! happy shooting.

I solved the stiff and sticky close ...but what causes the stiffness when opening after firing a round.

Unless you want to modify your Mosin those are pretty much your choices. If you don't mind modifying your rifle there are 2 other options you could check out: 1) Get an ATI scope mount kit. This will come with a standard Weaver style scope base & a turned down bolt handle, but it does require gunsmith installation. The receiver has to be drilled & tapped, and the bolt handle has to be cut off & replaced with the turned down unit. But you can use whatever scope you want to. (cont. in part 2)

pointing my rifles up and working the bolt slowly cures my hard to close bolts. Pointing them down and working the bolt slow results in a hard to close bolt every time. My T53 suffers the worst being that its the loosest and the rounds glide forward easier, my 91-30 being tighter keeps the rounds pushed against the bolt easier resulting in proper alignment of the rounds and gives me a better chance of a smooth bolt.

Thanks for the reply! I am thinking you're correct it's the tension in the bolt assembly post firing. I have done all the stuff related to sticky bolt (since it was sticking badly the first time I fired it). Unfortunately for whatever reason the range changed policy and I couldn't fire it after doing all the fixes the last time I went..

Mosin's rock. I'm still smoothing out my bolts. Thanks Chris your videos are the best. I really hope we don't end up like our German friend down there with these banned. That's when we'll know for sure there's no end to it. A bolt action five round rifle? What is more of a hunting gun than that?

Aaron It may need a bit of polishing on the bolt or you may still have some cosmoline in the wood that melts and seeps out when the gun gets hot. I'm not a gunsmith, but those are potential reasons I have heard that cause sticky bolts on mosins.

Oh I wish he would use soft jaws on a machined surface. Interesting solution, I shall examine the bolt on my Anchutz which presents a similar problem.

This and polishing my m38 lockingus made it go from not closing on a round to being one of the smoothest bolt guns I have

Y´all americans should be really proud of your gun laws and fight for it, or you end up like me doing this kind of job like in the video on your deactivated mosin. And I mean deactivated; they fucking killed it. Greetings from germany.

thanks Eric i have that problem but this will fix it ..

I like mine, I've had a little trouble with the mags feeding the rounds. But overall its pretty awesome.

I only fire handloads with my m44, only with PPU brass it happens that the bolt closes more difficult, with S&B brass I don't face this problem! Initially I thought I didn't size my brass deep enough, but I am also handloading for my shooting buddy's Mosin, his one's bolt is cycling flawlessly!

I'm reading a LOT of comments about having trouble opening the bolt AFTER firing a round. Folks....that lets you know you have an authentic Mosin. Eric needs to make a video on "how to make your bolt stick after firing" for those people who thought they got a real Mosin, but ended up with some smooth working copy. If it don't stick...it aint real.

Option 2) Turn your rifle into a faux WW2 sniper rifle using Accu Mounts' reproduction M91/30 PE scope & mounts along with a turned down sniper bolt handle. This will be more expensive than the ATI scope mount kit, and you'll be stuck with a 4x scope. However you will have a copy of Russia's WW2 PE sniper rifle, and it'll be legal in CMP Vintage Sniper matches. I really like mine! You can find the parts at accumounts dot you know the rest. You can also likely find all the parts on Ebay.

Mine is absolutely awful, can't wait to try this.

Grease the bolt parts and reassemble it. Mine did the same thing after about a hundred rounds last week. I just greased it and it worked great again.

What about the opposite of a tight bolt? I have one that rattles a lot. It’s smooth but when it’s opened all the way, it’s easy to move up and down. Just seems lose. Is this a good or bad thing ?

THANK YOU SOOOOO MUCH i did this to my mosin it dident quite work but it got me pointed in the right direction i ended up tapping the extractor out wards so it would work but then the round would not eject so i spent about 2 hours tapping the extractor inward and outwards over and over untill i got the bolt smooth and i got the rounds to eject every time ps you really souldent remove the ejector because it is such a tinny amount it needs to be bent and putting it in and out every time might bend it slightly were it will mess up the bending you did and it would take many many hours to get it right that way (from my experience)

I've had that problem with certain types of ammunition where the case was expanding and jamming inside after firing. I don't buy that particular type of ammo any more. It was a certain type of surplus ammo. I now like to only buy factory 188 (Novosibirsk) surplus ammo, and I haven't had any problems with that. You might have another problem though, I know my brother's M44 has a really sticky bolt after the gun heats up.

HELP! Eric what about the most effective long-range scope for a mosin 91/30? !? In my experience I have to choose between 1) a long-eye-relief handgun scope that doesn't hold well after a few shots with the kick/recoil of the mosin 2) a nice rifle scope that is set so far up & forward I'm always trying to aim with a halo effect jiggling around & the elevation screwed down to the lowest setting possible

check for machine marks and try to smooth them out. Mine had some very noticeable machining marks and i just took some 200 grit sand paper to them and wiped it down with oil and that seemed to help quite a bit.

i would love to see a more in depth version of a trigger job on a mosin

Use a brass brush and solvent, chuck it up in a drill and scrub the chamber out. Use a brush that fits snug in the chamber and your favorite solvent. It just takes a few passes and she'll be slick as snot on a glass door knob.

with all of these how to's on mosins, it would be interesting to have done all of these little projects on one rifle then compare it to one just out of the cosmoline.

Clay James 07-13-2008, 09:27 PM If it is easy to open when it's cocked and hard to open when its uncocked then its the camming surface between the cocking piece and the rear of the bolt. I had that issue with my 91/30 and polished it really nice and now it opens a lot easier. I also grease my Mosin bolts which makes them easier to work than with oil. -- going to check this.

@Jason Dunbar sounds like you have the same problem I do, pitted chamber. The brass expands into the pits when fired

If you don't have one of those files you can use sand paper. Use a high grit number like 1000 or 1200 to get a polishing effect.

Check their video library. He has already made a video on that.

That is caused by caked on cosmoline in the locking lug/chamber area. it usually expands when you are firing the gun, causing a sticky bolt.

Great Vids Eric very informative I'm trying to get my gun collection up myself only have 4 so far but I'm only 20 yrs old so I have enough time to get more. Keep up the good videos my favorites are the gun gripes but they are all great. I really want to go to the shop but I live far from it. Much respect Kyle from California (no right to bear arms)

Love your videos, but I noticed that you need at least one vise with a set of aluminum jaws, it comes in handy, it does not mar steel parts.

it could be a multitude of different things, the easiest to fix is cosmoline buildup, if there is excessive pitting in the chamber the cartridge could fire form to the chamber and become stuck, if there is a ring around the base of the bullet you could have cartridge seperation and the brass is expanding out of the chamber into the action, that means you have improper headspace,

i found your card at bestbreakfest and im very happy i did!

Grand, will definitely be doing this.

Another good video I love the Mosin rifles You gotta hell of a nice collection of them would like to see more videos on the Mosins. I have a M38 made in 1943 also have Nagant revolver made in same year. They are 70 years old and both run flawless. Gotta love it

Eric, I have noticed with my Mosins that If you feed a round into the chamber with the bolt and never let the round leave the face of the bolt as the round enters the chamber the bolts both close beautifully and just like your video shows! (esp after polishing my extractors) But if I put the round in the chamber by hand, or point the rifle down when chambering a round and gravity takes the bullet from direct contact with the bolt's face it makes my Mosins both hard to close.

We love you Eric

couldn't you also lightly file along the inside of the bolt face to remove light burrs?

great video I've encountered this problem and couldn't figure it out so thanks man

could be headspace or cosmoline in the chamber. check those first in order

if it hasn't been mentioned a coating of machinest blue applied to suspect tight spots will reveal exactly where they are so corrective action can be taken. an indicated tight spot may actually be at the opposite side of the indication. regards

Such a fine man you are, you have my respect.

Holy crap, I just thought that was how it was supposed to be. Thanks!

i watch all his vids on his last one doing a trigger job he said he was going to make a more in depth video but he hasnt yet thats what im talking about

The most delicate are the most important, how fitting.

My bolt is polished, my chamber area is completely clean and the advice of this video has been followed. Now, when I cycle my Mosin regularly, I have to slap the bolt handle down to lock it in, whereas when I slap the bolt forward during cycling, I can close the bolt easily. Ideas, thoughts or anything helpful would be appreciated.

I will definitely try this, the bolt on my mosin has to be slammed down to shoot it

Thanks for the info- My 91/30 works great, but the more I know the more I like my Mosin.

While I applaud the Mosin owners and at times would love to purchase one, my concern would be finding ammo in a SHTF WORL scenario. I have looked at them and they are stout machines, I do prefer the stock versions and have seen them at the range punch some very tight groups with iron sights.

Eric rules. Nuff said.

Nice stock!

I don't have a mosin yet, but when I get one I'll give it try.

Might have to do this to mine one of these days

Hey Eric I got the opposite problem. Seems like cocking or pulling the bolt back gives me grief. Its like the spring tension is extra strong. Do you recommend cutting the spring down to reduce the tension?

i dont watch every episode you put out.. but i do open the window and let it ply for a few seconds so you get my view count :D

Nice tricks... something to remember....

Great tip. Heck, even i could do this. Lol. No need to lap lugs or anything. Love all these videos

So i shot my 91/30 with the surplus ammo and the bolt was buttery smooth but then a week after i used the ppu 182 grain ammo and the bolt was pretty hard to open and close. Is it the ammo or the bolt?

I dont have a vise but, i sanded thr area with 60 then 100 the 600 then 1200 and it definaetly made a difference cyceling when loaded

Very useful video! Thank You ! 😁😁

my mosin closes fine... but opening it after a few rounds is a serious pain. Almost rubber mallet to wack it open. This is only after shooting a few rounds though. Cold bore dummy rounds operate just fine. Any ideas?