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Discussion Starter · #1 ·
Hey guys! So continuing with my Mosin technical questions. The 91/30 that I’m discussing in the bayonet thread is also stiff to close the bolt on a cartridge. Regardless of ammo type or case material. I scrubbed my chamber, cleaned the dried cosmoline where the extractor rides at the back of the barrel, and I disassembled and cleaned my bolt. So, there is one more thing. The extractor has a pretty good groove in the face of it, perhaps an early war part with a lot of rounds cycled with it? This rifle is 1939 dated Izhesk on the barrel and 1938 on the receiver tang.

BUT I MADE A DISCOVERY
It appears there is a bur on the edge closest to the cartridge wall and on cases cycled there is a definitive spot where the extractor took some brass out plus some minor shavings of brass.
3751224
 

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If you watch the cycling of the cartridge into the chamber , rising from below, the rim of the cartridge slides up under the extractor.
The extractor might rise a bit , under the tension of the rim, and that depends on how much room is between the bolt face and extractor.

The extractor in the picture looks like a round has been chambered and then the bolt closed, with the extractors forward face is marred from the rims scraping as the extractor raisied and pops over top of the rim.
The only time Ive broken a Mosin part is the extractor, while doing as I just described.
 

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Discussion Starter · #3 ·
If you watch the cycling of the cartridge into the chamber , rising from below, the rim of the cartridge slides up under the extractor.
The extractor might rise a bit , under the tension of the rim, and that depends on how much room is between the bolt face and extractor.

The extractor in the picture looks like a round has been chambered and then the bolt closed, with the extractors forward face is marred from the rims scraping as the extractor raisied and pops over top of the rim.
The only time Ive broken a Mosin part is the extractor, while doing as I just described.
Interesting, thank you. I have single loaded this weapon before as you described but not much. So I’m probably to blame. But this bolt has been stiff exactly like this my whole time owning it. So maybe it was marred before I got it? Anyway, I’m glad to know that now! So it feeds sort of similar to a Mauser 98? How can I fix this marring?
 

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Interesting, thank you. I have single loaded this weapon before as you described but not much. So I’m probably to blame. But this bolt has been stiff exactly like this my whole time owning it. So maybe it was marred before I got it? Anyway, I’m glad to know that now! So it feeds sort of similar to a Mauser 98? How can I fix this marring?
Maybe best to try a new extractor?

Mosin Nagant Bolt Extractor - Mosin Nagant Parts
 

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The basics Ive described and what I put here sorta apply to any and all makes of Mosin and thereof;
Theres a few places to look on the bolt, reciver, and lightly polish/oil.

Looking, you will see the brighter, rubbed , metal on metal contact areas. Some are working areas, some are just 'drag', especially on the rougher examples where polishing at the factory was minimal, mostly mid 40's makes.

The locking lugs contact areas you cant see inside the receiver ring can be cruddy, and lock up will feel that way..

Theres also need to examine, smooth if needed, and Lube the contact on the cam where the striker is cammed at the rear of the bolt with the cocking piece. When you raise or lower the bolt, this area is in contact and working against each other.

The bolt handles base, where it sets in against the receiver

Clean the inside of the bolt. crud and sand in there can make things grind.

Clean the interrupters blade ( it holds down the mags cartridges and lifts the top one for loading rim lock free....if its damaged or broken, it can sit badly in its slot and give you a grinding feeling as well.

Also, a dirty chamber can make for a grungy bolt feeling because the primary extraction is breaking a stuck case free from the chambers walls. a scrupulas cleaning in the chamber is actually the number one way to smooth out the extraction cycle of the bolt.

Good luck
 

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I had a problem with one of my Mosins where the bolt was hard to close on a round.On inspection there was a clear mark on the extractor where there was a high spot.
bit of work with one of my Mrs's fine emery nail files soon sorted it out and now the bolt closes as it should.
I
had another Mosin that had a bolt that would hang up when pushing the bolt forward, that turned out to be caused by insufficient clearance between the top of the magazine body and the bottom of the receiver and once the magazine body/trigger guard was shimmed the problem stopped.

If your bolt won't close on any ammunition, regardless of type or case material, and everything is clean I would consider checking the headspace just to be on the safe side.......
 

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Discussion Starter · #7 ·
Ok, thank you guys for all the advice I appreciate it. I won’t buy a new extractor for this exact rifle quite yet but I might get some just to have. I think I’ll try the polishing of it with a fine nail grinder board thingy and just see if I can smooth out the burr. Thanks again guys!
 

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So you could also just bend the extractor. You have to drive it out with a punch. I’d try brass first and if it won’t budge then use steel. It drives out to the rear from the bolt face. Fits via a tight dovetail. After you get it out lay it flat in a block of wood and place a steel punch right in the middle of it. Give it a sharp rap with a small hammer to give it less deflection into the bolt face. This technique also works well for adjusting the sear spring.
 

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The thing with my extractor was that it wasn't actually bent, it just had a high spot......hence the fettle with a fine emery board just enough until the bolt would close smoothly.I fettled it a bit, tried it and repeated as necessary without going overboard.
 

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Discussion Starter · #12 ·
Thank you so much guys! What is interesting is if I chamber a round with the rifle pointed upwards and the cartridge all the way back it’s a smooth chambering. No hang up. But when the rifle is level and the round in the magazine falls slightly forward then there’s a hangup on chambering.
 

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Nose dives....usually weak/broken Mag follower springs,(2 of em) or the front action bolt isnt tight, or the front of the mag isnt set properly to the bottom of the receiver.
2 of those things are just easily fix, usually from assembly, the first is pretty rare, but springs will sometimes sproing.
 

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So, one thing to remember about Mosins is the bolts are not ‘controlled feed’ like Mausers are. In other words, the cartridge does not slide beneath the extractor when it is stripped out of the magazine as in a Mauser. The extractor in a Mosin ‘snaps’ over the rim after the cartridge has been fully chambered. For this to happen smoothly, the extractor needs to have a beveled or ramped forward surface so it can ‘cam’ over the cartridge rim. Indeed, the cartridge rim has a beveled edge to aid this process. The extractor in the photo above has a dent or grove in it where it would contact the cartridge rim. This could be what is preventing the extractor from snapping over the rim — kind of like hitting a wall instead of a ramp. I suggest grinding out the dent so the extractor has a smooth ramp surface, which should smooth out your cycling issues.
 

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So, one thing to remember about Mosins is the bolts are not ‘controlled feed’ like Mausers are. In other words, the cartridge does not slide beneath the extractor when it is stripped out of the magazine as in a Mauser. The extractor in a Mosin ‘snaps’ over the rim after the cartridge has been fully chambered. For this to happen smoothly, the extractor needs to have a beveled or ramped forward surface so it can ‘cam’ over the cartridge rim. Indeed, the cartridge rim has a beveled edge to aid this process. The extractor in the photo above has a dent or grove in it where it would contact the cartridge rim. This could be what is preventing the extractor from snapping over the rim — kind of like hitting a wall instead of a ramp. I suggest grinding out the dent so the extractor has a smooth ramp surface, which should smooth out your cycling issues.
Unless I'm looking at them wrong the rims of the rounds slide up into the extractor as the bolt is moving forward on all my Mosins.....

In the video linked below at 3:35 the rim slides up under the extractor before the round is chambered.......

 

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I have to disagree with Tombstone, because the cartridge does rise under the exctractor, it does not snap over the rim.
The cartridge is controlled from the rising pressure of the mag follower, held in place by the interrupter and the rim cannot rise until its pushed past the long projecting wall on the right side of the receiver (looking down at it) 1/2 way forward in te receiver, looking down from the top, you will see two paths, one on each side that are angled froward and up as ramps to guide the cartridge and let the rim come up , into and underneath the extractor.

Load a round, pressed down untill its held in place by the interrupter, then slowly push the bolt forward and watch in slow mo....
If your poppig the extractor over the rim, you will see a mark on the back of the rim, if you load it properly from the magazine, there will be no extractor marks on teh cartridge's rim.

When I wrote about the nosedives, it was assuming you were placing the cartridges in the mag, held by the interrupter.
 

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You guys are looking at an ‘optical illusion’… The Mosin bolt head has a raised rim/shield that (except for the extractor and ejector groves) encircles the entire bolt head. Control feed rifles like the Mauser have a smooth un-rimmed bolt face on the bottom, allowing the cartridge rim to pop up beneath the extractor. The fully encircled raised rim of the Mosin will not allow the cartridge rim to be captured by the extractor. If it did, then you should be able to slide a bolt forward all the way (stripping a cartridge from the magazine), then, extract and eject the cartridge from the action without ever turning the bolt down into battery (like in a Mauser). If you do this in a Mosin, the cartridge will usually remain in the chamber, because the extractor has not ‘snapped’ over the rim. Now, if you strip a cartridge from the magazine, then slowly rotate the bolt into battery, you can hear the extractor SNAP over the rim of the cartridge. All my Mosins do this…

Happy experimenting…. Be safe.

TOM
 

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Interesting, Tombstone, it seems 2 out of 3 of my Mosins I tried will not have the rear of the cartridge seated in the bolt face, if I work the action slowly, untill I start the last 1/4th inch during camming with the bolt handle on its way down. It sort of gets broken down into stages when done that way. Also, when I have a cartride in the chamber and then I extract it partially, and then return to battery, I still get the same staged feel and sound, although the rim is definiltly under the extractor
Briskly cycling the bolt works much smoother and in one stroke. There are alot of variables with tha rim/extractor on that final 1/2 inch, if luck dosent allready have the rim under the extractor, then the cartridge is still shaky loose on the bolt face and not untill in battery is it firmed up.

I fingernail polished the rear of 3 cartridges, and theres no marks on the rear of the cartridges rims from the extractor if fed from the magazine, but definit marks when I plop a cartridge in the chamber and close it.
Proper use dosent take slow bolt strokes, but brisk ones, perhaps,while the rim is under the extractor somewhat while being placed into battery, its the camming into battery that sets the uncontrolled cartridge into place when cycled briskly.
I feel the rear of the cartridge slip into chamber, and being conical, the cartridge also being tapered, its not "firm" untill its cammed.
From what I have in fingernail polish, Im assuming theres some extractor on the rim , at least nothing contacting the rear of the rim,when being rammed into battery and the snap is the cartridge rim being finalized with the cartridges alignment and coordination into the chamber.
There is, on all my Mosins, a brighter side to the extractors face, on the right side, holding the gun, and that has to be contacting somewhere. I would expect to see a mark on the cartridge if the extractor was touching at that point, but thinking about it, it may be from contact with the rear of the chamber area.

And yes, Im being carefull , experimenting, Im here to learn and compare, get corrected and get better at all things Mosin :D
 

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It is probably accurate that extractor may often hang on the edge of the rim when chambered, then snap over the rim once the bolt is rotated down. Doing so should reduce the resistance a little when closing the bolt. But I believe the action was designed to enable the extractor to snap over the rim without any detrimental damage. The rim and extractor are beveled for this very function. If the extractor happens to hook on the edge of the rim before snapping completely over, than that's a bonus.. I also feel that loading a round directly into the chamber and closing the bolt should not do undue wear and tear on the extractor. If a bolt is significantly harder to close when inserting a round in the chamber, then the extractor may already be worn like the one in the OP’s photo. The dent or worn spot on the extractor in the OP's picture above is not all that uncommon on Mosin’s (see how many of yours have dents). Many of mine have worn spots on them in the exact location, and I almost never feed cartridges directly into the chamber. So either some owner before me loaded hundreds of rounds through many of my rifles directly into the chamber, or the rifle will pop the extractor over the rim as designed. I'm not sure if the dent (or worn spot) on the extractor is a cause of chambering cartridges directly into the chamber, or from the magazine, but it is definitely caused by the extractor hitting the rim. It may just be an accepted wear point in the design. I would think the larger the dent, the more effort it will take to close the bolt (unless the extractor is on the edge of the rim). Keep in mind that the material and heat treatment of any given extractor may vary widely, which may cause some extractors to wear quicker than others. A simple fix would be to simply re-surface the extractor with a Dremel tool and polish.

One thing to remember about Mosins is very few of them have the same parts on them as they did when they left the factory under "supervision". Most rifles have been cobbled together simply to make a complete rifle, and little attention was given to 'tune' any replacement parts for optimum operation. That especially holds true to the recent arsenal rebuilds that have flooded the market the past decade. Just because a rebuilt rifle looks purdy, doesn't mean they took the time to make sure it operated correctly.

Great discussion!!!!

TOM
 
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