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Old November 17, 2008, 09:27 AM   #1
azredhawk44
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Mosin Nagant action tuning

I've got a 91/30 that shoots amazing for a $60 rifle... I love going out and plinking with this thing. It's an absolute blast.

I've scrubbed at the chamber with a .30 caliber ratcheting chamber brush from an M14 kit, a .45 caliber bronze brush, warm soapy water to get rid of any corrosives and then Hoppe's #9 to remove all copper fouling from the bore and chamber. Disassembed the bolt, cleaned and oiled it, checking for rust or cosmoline anywhere.

I can work the action just fine... it's a bit stiff, and it takes a 2-whack technique to run this rifle quickly, but I can run it.

I had some friends shoot it this weekend though, and they were having problems. They aren't new to guns by any stretch, it was just the stickiness or tightness of the bolt that was causing problems for them.

I'd like, ideally, for this rifle to have a nice smooth action. I don't know if that's possible or not, but what can I do to ease it a bit? I don't see Russian soldiers in WWII movies having to double-whack the bolt to open the thing... it seems to open easily for them.

I think I've gotten the cosmoline out, but I guess one can never really be certain. I've heard that soaking the stripped action in gasoline will leech it all out of the metal's pores. Is this a recommended technique? What do I do with this gasoline afterwards... what is a safe way to dispose of it?

What other options are available to smooth this Mosin's action?
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Old November 17, 2008, 03:46 PM   #2
Jimro
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use brass cased ammunition instead of lacquered steel.

That usually works.

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Old November 17, 2008, 09:15 PM   #3
Kortik
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http://www.gunandgame.com/forums/mos.../?daysprune=-1
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Old November 26, 2008, 09:55 PM   #4
360 jp
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I don't think it will ever be an Enfield. I did all of that stuff, and my Mosin is still not "smooth". Enfields are known for their smooth actions and superb quality over the Mosin, IMO. They just are not as poweful as the Mosin, close though.
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Old November 27, 2008, 09:39 PM   #5
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I read somewhere that cutting off two or three coils from the firing pin spring will help Mosin "whack-itis". Mine had a case of this, but it got better after I made shims that fit between the sear and the reciever. Mine took a lot of shims, but the trigger pull is now about 6lbs and breaks clean, instead of 12lbs, creepy, and long. If I do my part, I can shoot 1" groups at 70-75yds!

Last edited by AutoPistola; November 27, 2008 at 10:32 PM.
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Old February 1, 2009, 03:07 PM   #6
Inventor81
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File work.

I caught the nagant bug a couple of weeks ago. I picked up an armory refurbished russian 91/30 from 1936.

In terms of an engineering standpoint, the nagant is superb in function, simplicity, durability, and reliability. I think it's a pretty gun as well, and am adding a few things to mine and two buddies' rifles, having had my mill and machining skill conscripted to the task of bringing our three nagants up to match specs.

I'll run through the mods that I've made - all are mild - and then the in-progress additions to the rifles. I'm using mine as a testbed since it came with a bent bolt handle, and am including a flickr link to a photo of mine and the friend's 91/30. The third rifle is a polish M-44, and I seriously doubt I can get it up to true match standards, but the same mods done to the 91/30's will likely help make it a bit more fun to shoot, and easier on the shoulder.

First, the action is slow out of the box. This is also rather unpredictable. Based on my initial evaluation of the rifle, without any further research, it appears that the rifle was cast, then rough machined, and hand finished with files and/or broaches. The tooling marks that are visible are clearly from non-finish grade mill bits/grinders and hand files - especially the nonparallel marks found in various places on the bottom inside of the receiver. Essentially the mods done to the receiver started with a thorough cleaning.

First I soaked a few cut up paper towels in lighter fluid/kerosene/paraffin - I made square wads that would fit over the cleaning rod and slide down the bore, about 2" by 4", folded in half to make a double ply 2 by 2 swab. DO NOT USE GASOLINE AS A SOLVENT.

The bore required several passes with the swabs - I think I got up to six passes just running the cleaning rod down from muzzle to chamber. There is a slight problem with doing this on a 91/30. The cleaning rod is shorter than the barrel by about a half inch, and until the wad clears the throat and pops into the chamber, the cleaning rod will be stuck. I had a piece of rigid plastic tubing that I threaded onto the end of the rod, which also helped keep the end from scratching the bore. I would recommend using a similar technique when cleaning just so you don't have to lap the bore if it's already in good condition.

My rifle appears to have been unfired. Either that, or it was maintained ungodly well for over 72 years.

The next step was to use some bent nose forceps (kelly clamp would work well in this situation) to swab the chamber. I passed a large wad in and out of the chamber repeatedly and got all the cosmoline out - I then went over the entire rifle with solvent soaked swabs, then dry swabs, and applied a thin layer of linseed oil inside and out before storing it for the next 24 hours.

Also of note, my stock had been sanded down, and my barrel, reciever, and bolt (the steel parts) are all magnetized. Yes, magnetized. ***?

Anyhow, due to the sanding, the stock was totally dried out and a bit too light looking for my taste, so as a blacksmith I turned to my trusty linseed oil. The wood wound up soaking up about six coats of oil within 10 minutes of application, until the last one took about two hours to fully soak in. These were applied with paper towels, and excess oil was removed from metal parts so as to leave only a thin film and not varnish up the surfaces. Prior to application of the oil I sanded and polished the brass/steel sling fittings which were previously badly scratched from the stock sanding operation.

The oil tightened up the stock nicely, with the wood swelling nicely towards original spec, and took on a nice honey/khaki color that matches the wood floors in my home. Real pretty ;-) I covered it in bowling alley wax, which soaked in and left a nice, rich matte sheen on the wood. If your finish is totally crappy and bumpy, feel free to sand and apply this finish - it worked perfectly and you wind up with a rather different looking nagant.

The mechanical mods mostly consisted of removing the "bluing" from the inside of the reciever. I removed and polished the magazine follower on 4000 grit SiC wet/dry sandpaper with a few drops of tap magic machine oil. This results in loose particles of carbide abrasive, so please remember to rinse your part in solvent and clean with a lint free cloth prior to installing it back in the rifle.

I also noticed the action required roughly 25 seconds to cycle and dry-fire through the five rounds. The procedure used to diagnose and treat the problems was a light sanding with some 1600 grit SiC paper - VERY light - which gave a slight surface fuzz on the metal - very light scratches. When I rinsed away the abrasive and re-cycled the action a few times, I pulled the bolt and could easily see witness marks where the bolt rode on the receiver. I simply polished the mating surfaces on the reciever with 4000 grit paper wrapped around a flat rat-tail file to keep things straight and true, and the bolt got a light polish and all burs and outside non-bearing edges were broken to about a .2mm radius for comfort/fit/finish. The critical component in the whole action which will slow you down is the corner between the bolt slot and the ejection port where the bolt handle folds down when ready to fire. The corner on mine was very sharp and unevenly filed, so I had to go through about five polish/cycle/witness routines until I got it nice and evenly matched to the mating surface on the bolt. I would caution to not remove much material and focus on contouring the corner to about a 2-3mm radius ONLY AS NEEDED to allow the bolt to slide forward and down over the corner with ease. there was also a small bur on the bolt at this location, and some spalling which I removed and polished, and I could at this point cycle and dry fire 5 times in just under 11 seconds.

I have polished the inside of the magazine mostly because it had a bunch of crud in there that the solvent didn't seem to kick - it appears to be lacquer/varnish overspray and drips that just made it look icky - so i cleaned it up.

The second sticking point in the action was the rearmost notch on the inside of the bolt carrier/receiver channel. I think this is where the base of the rimmed cartridge, or the stripper clip, would pass when loading it from the top. In any case, the muzzle-end of this bluff surface was a bit higher than the otherwise parallel surface that the bolt rode on, so while pulling the bolt back, the handle carrier bound against the corner. I removed the bur with a file, and re-polished with 4000 grit paper. This enabled me to reliably cycle and dry fire 5 times in just under 10 seconds. The action is slightly sloppier, but just as smooth-riding/unbinding as my 1945 long branch Enfield.

At this point the linseed oil was dried out and gummy, and had served the purpose of preventing oxidation to freshly polished surfaces while I waited for the weekend to arrive, so I re-cleaned everything with a mix of kerosene and WD-40, then straight kerosene, and have since plugged the barrel and chamber with foam earplugs to prevent oxidation down the bore while I set up for further mods.

Next step: Muzzle brake and custom bipod. These will both take some time since I'm doing a custom box-style muzzle brake with some engine turning on it. If you want a brake, I totally recommend the commercial 20 dollar unit you can find allllllllll over the internet. Grab one and go easy - this is a "my baby" rifle, so I'm milling my own and making it pretty.

Also, the bipod is a scratch fabrication, so I'm doing engine turning on the adjustable steel legs, brass saddles (clamping it over the forearm instead of the end of the barrel to limit vertical loading and bore deformation). These will have a spring loaded bit to keep them folded back against the rifle just fore of the hand-grip area, and a two-position ball detent to hold them in place when folded or deployed. I do not have, nor want, a bayonet - it will soon have a picatinny rail mounted to the side of the receiver, and I'll be forwarding photos soon of the forging/machining operations.

I recommend against using the machined aluminum mounts that replace the rear sights - these are flexible and rather unstable and subject to zero-drift since it's a clamp system, not a threaded connector that screws into the receiver.

Anyhow, sorry for the long post, but I'm a bit excited and didn't realize how much I'd done to the rifle in just three evenings.

Here's the link, and thanks for reading!

http://www.flickr.com/photos/8887425...n/photostream/
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Old February 3, 2009, 08:31 AM   #7
lfmayor
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Dremel

LOL, yeah, I understand that word dremel scares many of you here but what I did was take my 3 m-44's and use the felt wheels and "eraser" tips to shine up my bolt, sear, raceways and what I could reach of the chamber. I used that red wax polishing compound that Dremel supplies in their polishing kits and took my time.

None of them are quite like jeweled Sako custom actions, but it did help considerably and was especially noticeable in the two I scoped.
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Old February 4, 2009, 12:10 AM   #8
croc4
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give the bolt parts a good spit and polish.

Take the bolt apart and polish the mating surfaces of the bolt, I did this on mine and it smoothed the opening/closing of the bolt quite a bit, also give it a good lube. My bolt has a number of machine marks that tended to catch after firing, the slight polish and lube corrected this.

But bottom line is as you noted a $60 rifle, I have several that I have converted to sporters, and while group wise they stand toe to toe with a lot of rifles I see at the range, they are still only a $60 dollar rifle. Much like a mazda to a bently, the mazda may do everything and more, but it aint no bently



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Old December 4, 2012, 10:02 PM   #9
zbones6
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maybe i just got lucky, but once i cleaned all the cosmoline out of the rifle, cleaned and oiled it, my action works perfectly. i dont know about your rifles, but mine has all matching numbers. i think the matching bolt and action really makes a difference
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Old December 6, 2012, 07:45 AM   #10
iraiam
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I have the same problem with my both my Mosins, I cannot work the action while the rifle is still shouldered due to my left elbow and wrist problems, I have to lower the rifle off my shoulder and cycle.
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Old December 6, 2012, 08:24 PM   #11
tobnpr
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If running the bolt gets stiffer when hot- you've still got residual cosmoline in the chamber. a 12 ga. brush chucked in a cordless drill works wonders here...

If it's stiff all the time, polish the mating surfaces inside the bolt.

Shouldn't have to whack it, to run the bolt...

My sporterized MN bolt runs almost as smooth as my Savage (which aren't known for smooth actions...), nothing like a Rem 700 though...
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