The Russian Mosin Nagant Forum

Hello everyone. I will try to be as detailed as I can in my post.



Recently I have been having trouble where the bolt will not close on a round unless I use really muscle/slap it. The bolt operates smooth and fine without any rounds though.
This occurs regardless of a full magazine with 5 or 1 in the magazine.

My Mosin has not always been like this, I've had about 300 rounds through it spread across a handful range visits and this has never happened up until recently. I've shot a mixture of brass cased and steel cased ammo. it has not seen any corrosive surplus just yet.

I have gone through as many procedures of cosmoline removal on my mosin. Boiling hot water, degreaser, checking the chamber for burrs, using a 20g and brushing the chamber..etc. Headspacing was fine as I had it checked and fired a few hundred rounds through it.

After doing extensive research through youtube and google i came upon this video: http://www.youtube.com/watch?v=JXRFBNbTl9I so i brought my bolt head to a gunsmith and asked if he could do what was done in the video, however he felt uncomfortable hammering out the bolt head so he took a dremel to the part of the rim on the bolt head that looked bent inwards and sort of polished it and made it thinner. so instead of hammering it outwards like the video suggested he took a dremel and polished/thinned it out.

i have come to a conclusion of sorts that my extractor was out of spec/bent or that the rim of my bolt head was slightly curved/bent inwards in one small area. not enough clearance? i also noticed a horizontal groove/indent across the face/top of the extractor possibly from the rim of the cartridge not going underneath and the countless times i force/slapped/punched my bolt closed.

the extractor seemed like it was too tight or bent inwards, i tried putting a round on the bolt face(disassembled from the bolt of course for safety) and really had to rotate it/wedge it in and force it for the extractor to go over the rim and for the rim of the cartridge to be seated in the bolt face. so I tried removing the extractor yesterday and broke it, so i'll be needing a new extractor. Now without the extractor my bolt seems to close just fine on a round. but of course i cannot extract it because of no extractor.
now before i broke the extractor trying to remove it, i tried bending it slightly outwards with a flathead screwdriver and it seemed to have fixed the problem but i realized i bent it too far out because now the rounds wouldn't extract, that is why i tried removing it to try and bend it back in but i ended up breaking it



i have the following questions:
-with what the gunsmith did above to the rim of my bolt head will this affect anything such as headspace or operations? the rim of the boltface that had the dremel seemed to have become a tiny bit shorter in depth and considerably thinner
-how much force is needed for the rim of the cartridge to be seated into the bolt face under the extractor? i tried manually putting it in before i broke the extractor while removing it and it wouldn't fit unless i really wedged it/rotated it in there with a lot of force
-could the horizontal groove/indent across the top/face of my extractor been the culprit? the rim sits into the groove making it hard for me to close the bolt without needing force to jump the groove/indent?
-is it possible there wasn't enough clearance from the extractor to the bolt face or the rim of the round to catch making it hard to rotate/close the bolt?
-Should I just buy a new extractor?(where is the best place if so)
-Should I buy a new bolt face w/extractor and if i were to do so, I would need to get my headspace checked out I imagine? is it a guarantee that changing the bolt face will affect headspace? if what the dremel did to the bolt face rim affects headspace/function?
-regardless of if i buy a new extractor or new bolt face/extractor, should i make some modifications/sanding/filing to the extractor? before installing?
-my rifle functioned fine for a few hundred rounds, so something must have caused this issue in terms of my bolt not closing on a round, is there a chance my extractor or bolt face goes out of spec again down the road?
-is it possible that there is something inside of the chamber that i overlooked? a hidden burr of some sorts that caused all this considering my rifle and bolt functioned fine closing on rounds until recently? i have looked with a long bore light down the barrel, down the chamber, put my fingers in there and could not find anything abnormal

here are two pictures of what my bolt face currently looks like after the dremel job: apologize for the links, the images seem to be too big to embed into the thread.

the upper right corner of the rim of the bolt face you can see has become thinner as a result of the dremel


you can see a little better here what the inside edge of the rim looks like on the bolt face where the dremel was used


thanks everyone

its the ejector.. I had the same problem. I couldn't find just the ejector so I got a new bolt head. problem solved.. check the head space.

jb

Wow. That was quite a detailed post. It sounds like you just needed to replace the extractor, or swap out boltheads (with extractor).

jeremyb wrote:its the ejector.. I had the same problem. I couldn't find just the ejector so I got a new bolt head. problem solved.. check the head space.

jb

thanks, i just don't have the money to get those gauges to check headspacing. i wonder if gunsmiths would charge for checking headspace.
did you have to file/sand or do any modifications to your new extractor/bolt head?
im afraid when i replace my extractor the same problem would happen again down the road especially because my rifle was fine for the first 300 rounds or so

millman wrote:Wow. That was quite a detailed post. It sounds like you just needed to replace the extractor, or swap out boltheads (with extractor).

thank you.

Welcome to the forum Steve. Unfortunately you put the horse before the cart. Before you tried anything and in the future it's a good idea to ask about it here first especially before modifying parts. I know that may not have been possible if you only just found us but in the future make a post if you have problems and we'll be able to walk you through checking it and repairing the problem. It might not be a simple answer because these rifles, like most mechanical things, have many variables that can be at play. In this case I believe the problem you're experiencing is what was stated above, the extractor. Especially after seeing this. " i also noticed a horizontal groove/indent across the face/top of the extractor possibly from the rim of the cartridge not going underneath and the countless times i force/slapped/punched my bolt closed." This is easily fixed by either replacing the extractor or carefully honing the face smooth again with very fine file or wet-stone. Remember when a round is chambered the bolt face is pushing it from the magazine into the chamber but the extractor doesn't clip over the rim until the round is almost completely in the chamber. If there's a groove in face of the extractor like you state the will make it harder for the extractor face to override the rim and will try to catch.

One way to check this is to first remove the bolt from the rifle. Then use a dummy round installed in the face of the bolt (with the rim already under the extractor) before trying to chamber the round therefore bypassing the step of the extractor overriding the cartridge rim. I say to use a dummy round because a spent case won't work because they're usually expanded, don't chamber well if at all and a live round would be very dangerous because the bolt would be cocked and could discharge. One other thing you could do is simply chamber a round until it is fully seated with the bolt handle in the seated position as if the rifle was ready to fire. Then move the bolt back up as if you're going to extract the round and the handle pointing upward. Pull the bolt handle back slightly about one half inch, stop. Then rechamber the round pushing the bolt back forward and down in the seated position as if you were going to fire the rifle. If the round rechambers easily the problem is the extractor. I caution you this should be done in a safe place as if you were going to fire the rifle with the muzzle pointing in a safe direction. One other way to check this would be to simply remove the extractor and reassemble the bolt and see if you have a problem chambering a round. Also make sure the extractor isn't pushed in towards the center of the bolt face to far. The back side of the extractor should be even with the outside of the bolt head.

Here's a follow up to what you originally posted. I read more of the post and I see where you did some of what I suggested above and it seems the extractor was the problem. I also see you used a dremel on the bolt head. Youtube is a great place to research....sometimes. Be very careful about what advice you take from it. You need to replace the extractor at a minimum but might need the bolt head too. I'm not sure how damaged it is now from the pictures. Both the extractors and bolt heads with extractors are listed here. https://www.libertytreecollectors.com/p ... ategory=17 If you replace the bolt head, headspace should be checked. A gunsmith will likely charge you unless you have a working relationship with him. Maybe he'll be a nice guy and hope you'll bring him more work and not charge you. Here's headspace gauges http://www.okiegauges.com/sales.html and you'll need the field gauge at a minimum but should have the no-go and field. Don't look on ebay for them either those are poorly made counterfeits of these gauges. The field gauge is only $25 delivered and once you have it you'll never have to worry about checking any new Mosin Nagants you get. It will pay for itself trust me.

thank you weldon. i absolutely put the horse before the cart. i acted upon this issue very prematurely with very little preparation. :(


at this point it would be safer to just replace the entire bolt head w/extractor? it wouldn't be worth it to risk anything with the results of the dremel job on the bolt head? a part of the rim on the bolt head has lost a considerable amount of thickness as shown in the pictures and a little bit of depth as well(it seems shorter or dremeled down than the rest of the circular rim/frame.
the depth of the circular rim/frame from the bolt face is what ultimately affects headspace I would imagine? since the rim of a cartridge would be sitting inside the rim/frame of the bolt head to the bolt face? or is head space specifically from the bolt face to the chamber face? im a bit confused.

also what are the chances that a replacement bolt head w/extractor is out of spec in terms of headspace? are the odds good or bad in terms of headspacing issues with the replacement i would be buying?

i am also a bit worried that the new bolt head w/extractor i buy would have similar issues or just by bad luck the extractor on the replacement would become out of spec again. maybe i should buy a new bolt head w/extractor and an extra extractor? on new replacement bolt heads/extractors..etc should i bother with modifying it at all in terms of sanding/filing or leave it as is and hope for the best and handle modifications as problems arise?

steveholt wrote:thank you weldon. i absolutely put the horse before the cart. i acted upon this issue very prematurely with very little preparation. :(


at this point it would be safer to just replace the entire bolt head w/extractor? it wouldn't be worth it to risk anything with the results of the dremel job on the bolt head? a part of the rim on the bolt head has lost a considerable amount of thickness as shown in the pictures and a little bit of depth as well(it seems shorter or dremeled down than the rest of the circular rim/frame.
the depth of the circular rim/frame from the bolt face is what ultimately affects headspace I would imagine? since the rim of a cartridge would be sitting inside the rim/frame of the bolt head to the bolt face? or is head space specifically from the bolt face to the chamber face? im a bit confused.

also what are the chances that a replacement bolt head w/extractor is out of spec in terms of headspace? are the odds good or bad in terms of headspacing issues with the replacement i would be buying?

i am also a bit worried that the new bolt head w/extractor i buy would have similar issues or just by bad luck the extractor on the replacement would become out of spec again. maybe i should buy a new bolt head w/extractor and an extra extractor? on new replacement bolt heads/extractors..etc should i bother with modifying it at all in terms of sanding/filing or leave it as is and hope for the best and handle modifications as problems arise?

In my opinion that bolt head is questionable now and I would change it. It may not give you problems but it's been modified in a critical area, where the rim is supported. The problem is if you buy a replacement, headspace will need to be checked and the replacement bolt head might be out of specs. for that rifle but might pass on another. Sometimes you need try a few, sometimes you get lucky and find one that works the first time. This is how most guys fix a rifle with headspace problems. Simply swapping them around from one rifle to another can make one pass that didn't before and the one the bolt head came off still pass. Do Not File or sand anything to make this pass headspace. You really need to forget about that. Unless you're a gunsmith or have some mechanical background you really should rethink doing modifications like you did to that bolt head. This problem was most likely as simple as an extractor problem that is now getting into other problems. What I would do is get another bolt head with extractor and go from there at this point. If you have a similar problem with chambering it can be addressed by starting here before you do anything further. You're going to need a headspace gauge now too. Either that or take it to a gunsmith and let them fix it if you don't feel confident going further at this point. Below is an illustration compliments of bunkysdad that shows what headspace is in a generic way.

WeldonHunter wrote:

steveholt wrote:thank you weldon. i absolutely put the horse before the cart. i acted upon this issue very prematurely with very little preparation. :(


at this point it would be safer to just replace the entire bolt head w/extractor? it wouldn't be worth it to risk anything with the results of the dremel job on the bolt head? a part of the rim on the bolt head has lost a considerable amount of thickness as shown in the pictures and a little bit of depth as well(it seems shorter or dremeled down than the rest of the circular rim/frame.
the depth of the circular rim/frame from the bolt face is what ultimately affects headspace I would imagine? since the rim of a cartridge would be sitting inside the rim/frame of the bolt head to the bolt face? or is head space specifically from the bolt face to the chamber face? im a bit confused.

also what are the chances that a replacement bolt head w/extractor is out of spec in terms of headspace? are the odds good or bad in terms of headspacing issues with the replacement i would be buying?

i am also a bit worried that the new bolt head w/extractor i buy would have similar issues or just by bad luck the extractor on the replacement would become out of spec again. maybe i should buy a new bolt head w/extractor and an extra extractor? on new replacement bolt heads/extractors..etc should i bother with modifying it at all in terms of sanding/filing or leave it as is and hope for the best and handle modifications as problems arise?

In my opinion that bolt head is questionable now and I would change it. It may not give you problems but it's been modified in a critical area, where the rim is supported. The problem is if you buy a replacement, headspace will need to be checked and the replacement bolt head might be out of specs. for that rifle but might pass on another. Sometimes you need try a few, sometimes you get lucky and find one that works the first time. This is how most guys fix a rifle with headspace problems. Simply swapping them around from one rifle to another can make one pass that didn't before and the one the bolt head came off still pass. Do Not File or sand anything to make this pass headspace. You really need to forget about that. Unless you're a gunsmith or have some mechanical background you really should rethink doing modifications like you did to that bolt head. This problem was most likely as simple as an extractor problem that is now getting into other problems. What I would do is get another bolt head with extractor and go from there at this point. If you have a similar problem with chambering it can be addressed by starting here before you do anything further. You're going to need a headspace gauge now too. Either that or take it to a gunsmith and let them fix it if you don't feel confident going further at this point. Below is an illustration compliments of bunkysdad that shows what headspace is in a generic way.

would i be better off just buying a new rifle and selling this one for parts? with the estimated costs of what i have to spend on multiple bolt heads w/extractor if the headspace is no good on the first one and the headspace gauges? knowing my luck i probably wont get lucky with my first bolt head w/extractor replacement :(


in terms of the filing/sanding i was considering that in case i have problems in the future of closing the bolt again, smoothing out the extractor so there are no grooves..etc and not to pass headspace?

Just order a bolt head with extractor. Odds are that it will headspace fine. You will need a headspace gauge, but this is advisable in any case.

i was running my finger inside the chamber very carefully and felt something abnormal, a small burr or something jagged on the lower right side of the chamber area.
after doing some estimations with where on the bolt head that abnormality in the chamber would touch, i figured out that when the bolt rotates right the jagged bump/burr would actually hit the extractor on the bolt head.
i think this is what caused the extractor to bend out of spec and inwards and eventually caused the horizontal groove on my extractor face and through repeated use of forcing the bolt made it worse.

not exactly sure how to get that jagged bump/burr out? i mean it is nothing major but a tiny jagged bump to the feel of my fingers when running my finger in the chamber and rotating it as if my finger was a bolt...

what exactly causes jagged bumps/burrs in the chamber if it wasn't there originally? the chamber was fine originally when firing a few hundred rounds through it so something must have happened for that jagged bump/burr to appear inside the chamber. was it part of the chamber originally? or accumulated scrap from casings/ammo?

steveholt wrote:i was running my finger inside the chamber very carefully and felt something abnormal, a small burr or something jagged on the lower right side of the chamber area.
after doing some estimations with where on the bolt head that abnormality in the chamber would touch, i figured out that when the bolt rotates right the jagged bump/burr would actually hit the extractor on the bolt head.
i think this is what caused the extractor to bend out of spec and inwards and eventually caused the horizontal groove on my extractor face and through repeated use of forcing the bolt made it worse.

not exactly sure how to get that jagged bump/burr out? i mean it is nothing major but a tiny jagged bump to the feel of my fingers when running my finger in the chamber and rotating it as if my finger was a bolt...

what exactly causes jagged bumps/burrs in the chamber if it wasn't there originally? the chamber was fine originally when firing a few hundred rounds through it so something must have happened for that jagged bump/burr to appear inside the chamber. was it part of the chamber originally? or accumulated scrap from casings/ammo?

Steve I have to go pick someone up at the airport so this will have to be short and I'll elaborate when I get back later tonight. First off don't sell the rifle for parts. I was just pointing out that swapping the bolt head will fix this but you may have to get more than one. As millman stated you'll probable do ok with the first one. You will need to recheck headspace. That burr you're talking about is most likely the extractor channel and they are rough. The picture below is the best one I have to show what they should look like.

jeremyb wrote:its the ejector.. I had the same problem. I couldn't find just the ejector so I got a new bolt head. problem solved.. check the head space.

jb

Ditto, complete bolts are somewhat inexpensive, and we as collectors should have at least one or two to select and replace defective problems.

Although, I must admit I haven't encountered a problem as you described.

Hope it worked out for you!

Whew, long post. The dremal IMHO trashed the bolt head - you would have been better off lightly punching the rim if bent over with a punch. After all, we are talking about thousandth's of an inch.
The dremal removed way too much material. I would not use that bolt head. So, you need a bolt head and extractor. Purchase those from Liberty Tree and 99% of the time you won't have any headspace issues. If you do buy another one.

WeldonHunter wrote:

steveholt wrote:i was running my finger inside the chamber very carefully and felt something abnormal, a small burr or something jagged on the lower right side of the chamber area.
after doing some estimations with where on the bolt head that abnormality in the chamber would touch, i figured out that when the bolt rotates right the jagged bump/burr would actually hit the extractor on the bolt head.
i think this is what caused the extractor to bend out of spec and inwards and eventually caused the horizontal groove on my extractor face and through repeated use of forcing the bolt made it worse.

not exactly sure how to get that jagged bump/burr out? i mean it is nothing major but a tiny jagged bump to the feel of my fingers when running my finger in the chamber and rotating it as if my finger was a bolt...

what exactly causes jagged bumps/burrs in the chamber if it wasn't there originally? the chamber was fine originally when firing a few hundred rounds through it so something must have happened for that jagged bump/burr to appear inside the chamber. was it part of the chamber originally? or accumulated scrap from casings/ammo?

Steve I have to go pick someone up at the airport so this will have to be short and I'll elaborate when I get back later tonight. First off don't sell the rifle for parts. I was just pointing out that swapping the bolt head will fix this but you may have to get more than one. As millman stated you'll probable do ok with the first one. You will need to recheck headspace. That burr you're talking about is most likely the extractor channel and they are rough. The picture below is the best one I have to show what they should look like.

thanks, i think ill go ahead and throw this bolt head out since the dremel took a bit too much off. then ill order a new replacement bolt head w/extractor and go from there.
if i were to keep this existing bolt head with the dremel job because the headspace is correct on it and just replace the extractor, in your opinion would it be unsafe or anything because of the dremel job?

steveholt wrote:

WeldonHunter wrote:

steveholt wrote:i was running my finger inside the chamber very carefully and felt something abnormal, a small burr or something jagged on the lower right side of the chamber area.
after doing some estimations with where on the bolt head that abnormality in the chamber would touch, i figured out that when the bolt rotates right the jagged bump/burr would actually hit the extractor on the bolt head.
i think this is what caused the extractor to bend out of spec and inwards and eventually caused the horizontal groove on my extractor face and through repeated use of forcing the bolt made it worse.

not exactly sure how to get that jagged bump/burr out? i mean it is nothing major but a tiny jagged bump to the feel of my fingers when running my finger in the chamber and rotating it as if my finger was a bolt...

what exactly causes jagged bumps/burrs in the chamber if it wasn't there originally? the chamber was fine originally when firing a few hundred rounds through it so something must have happened for that jagged bump/burr to appear inside the chamber. was it part of the chamber originally? or accumulated scrap from casings/ammo?

Steve I have to go pick someone up at the airport so this will have to be short and I'll elaborate when I get back later tonight. First off don't sell the rifle for parts. I was just pointing out that swapping the bolt head will fix this but you may have to get more than one. As millman stated you'll probable do ok with the first one. You will need to recheck headspace. That burr you're talking about is most likely the extractor channel and they are rough. The picture below is the best one I have to show what they should look like.

thanks, i think ill go ahead and throw this bolt head out since the dremel took a bit too much off. then ill order a new replacement bolt head w/extractor and go from there.
if i were to keep this existing bolt head with the dremel job because the headspace is correct on it and just replace the extractor, in your opinion would it be unsafe or anything because of the dremel job?

In my opinion yes that bolt head could be unsafe. Replace it, check headspace and go from there. Yes you're going to have to get a headspace gauge. Don't use a damaged bolt head just because it passes headspace. Don't skimp on safety. You have no choice at this point.

If I read the original post correctly, it was a gunsmith that modified the bolt in an unsafe way. I'd say the gunsmith owes you a new bolt head. If the gunsmith is affiliated with a gun store, he may have a selection of bolt heads to swap around to get the headspace correct.

I'm not sure about this gunsmith. He should know that removing material from any bolt is not a good idea. The engineers who designed this bolt put that metal at that thickness and depth on the bolt head for a reason. He might have some parts laying around and provide them for you. You could then try it out in your rifle and have him check the headspace. Only problem there is that conventionally (not using a coin type flat gauge like the Okie), is that he would have to remove your extractor. I, personally, wouldn't want him touching this bolt again. So, I would still by-pass this guy and get a bolt head or two, w/extractor, from Liberty Tree and a no-go gauge from Okie. If you are going to play in this sandbox there are some basics you need and one is at least a no-go gauge. The chances are high that this is not your last Mosin.

soylentblue wrote:If I read the original post correctly, it was a gunsmith that modified the bolt in an unsafe way. I'd say the gunsmith owes you a new bolt head. If the gunsmith is affiliated with a gun store, he may have a selection of bolt heads to swap around to get the headspace correct.

Yeah I see that now. I totally skimmed over that part. The problem is it's kind of hard to tell what it looks like from the pictures. Having it in hand would be the best way to make a good assessment. From what I do see it looks amateurish and I err on the side of caution especially when offering advice via a forum post. I still say replace it just to be safe. It's in the most critical area of the rifle and supports the cartridge as it's being fired.