How to Buy and Clean a Mosin-Nagant Rifle
June 17, 2016
The days of the $12 Mauser are long gone, but there are still some pretty good deals to be had, and if you're not afraid to get your hands dirty, plenty of opportunity to open up new worlds. One such rifle is the Mosin-Nagant.
Mosin-Nagant and SKS rifles are the current leaders in the field of entry-level bang-sticks, and you can easily find them at a good price in shops, at gun shows or in the pages of Firearms News. My friends at J&G Sales in Prescott, Arizona usually have a good selection of these popular rifles in a variety of grades.
Having worked at J&G while I was in college, I have a certain affinity for the place, and they are always my go-to source for milsurp project guns, ammo and accessories, so when I decided to tackle a Mosin-Nagant, that's who I called.
Picking Your Mosin-Nagant
When you buy a Mosin-Nagant, or any milsurp rifle, it will almost always come with an extra helping of cosmoline, a sticky, waxy, brown grease that is used to protect guns in storage from rust and corrosion.
If you're ordering the Mosin-Nagant in, you don't get a chance to inspect in advance, but most places like J&G will have their guns segregated into different grades at different prices, and for a nominal fee — usually from $10 to $30 — they will sort through to find one that meets your specific needs. If you're just looking for a shooter to tinker on, the only critical areas of concern are the bore and chamber. Everything else can be repaired or replaced relatively easily.
As inexpensive as these Mosin-Nagant rifles tend to be, the parts tend to be even cheaper. So if there is pitting in the bolt face, a replacement bolt or just the bolt head, can easily be had. If the trigger is terrible, that can be improved or replaced for just a few bucks. If the stock is cracked, it can usually be repaired, or you can get a good factory stock at a good price. There are also aftermarket stocks available for a few bucks more. A chewed up crown can be recut. A stiff bolt can be smoothed. Damaged sights can be replaced or repaired.
There's really not much on these Mosin-Nagant rifles that can't be handled at the kitchen table or in the average garage — without expensive specialty tools or fancy machinery. It's up to you to decide just how much tinkering you're interested in doing. Select your gun accordingly, keeping in mind that the more tinkering a gun is going to require, the lower the price should be.
Personally, I much prefer a gun that needs some attention. Even my new guns get a thorough going over, smoothing, polishing and personalizing. This helps me to be really familiar with my guns, and it gives me confidence in their fit and function. With older milsurp guns, it's as much about honing my skills as it is about tuning the gun, and there's a definite sense of satisfaction in turning a grease-soaked mess into an attractive, reliable shooter.
If you're heading out to your local shop or a gun show with the intention of bringing home a new-to-you Mosin-Nagant, do yourself a favor and do a little research on the various types, styles, and countries of origin, so you have an idea of which versions you think you'd prefer, and what they normally sell for. Be sure to take shipping and FFL costs into account when you're pricing rifles from a big volume dealer. That stuff can add up quickly.
Also, take some supplies with you. I recommend a pair of rubber gloves, a couple of paper towels, a .30 cal. bore snake and a small flashlight. A "No Go" gauge to check headspace isn't a bad idea, if you have one. They're not expensive, and if you're going to get serious about tinkering with Mosin-Nagant rifles, it's a worthwhile investment. Often the seller will have a "No Go" gauge available for you to use.
Check the bore and chamber carefully for pitting, rings, or corrosion. Clean it if you have to. You need to be able to see sharp, even rifling, and a smooth chamber. If you can, use a "No Go" gauge to verify that the bolt won't close on it. Make sure that the bolt face and the rim of the chamber are good and clean before testing.
Don't worry about testing with a "Go" gauge or a "Field" gauge. The "Go" gauge doesn't really tell you anything unless it's a brand new barrel, and the "Field" gauge only tells you that the gun is minimally safe to shoot. Stick with the "No Go" gauge. As long as the bolt won't close on that, you know it's safe and has some life left in it.
Beyond that, point out every little flaw you can find in the Mosin-Nagant to try and talk the seller down a bit, and only buy it if you're confident that you want to tackle, or don't really care about those flaws.
One other area you might want to give some special attention to is the trigger and sear. Open and close the bolt several times with gusto to see that the striker doesn't fall on its own. With it cocked, wiggle and jiggle the knurled cocking knob to see if you can make the striker fall without touching the trigger. Dry fire and feel the trigger to ensure that the sear is engaging solidly.
On Mosin-Nagant rifles, you can actually watch the sear travel as you pull the trigger. Shine a flashlight under the cocking knob and you can see the sear block on the bottom of the bolt. At the front of that, you can see the trigger sear and watch it as it slides down when you slowly squeeze the trigger. You want to see that sear move at least the thickness of a business card before it releases the striker.
Next, pull out the bolt by holding the trigger as you slide the bolt out the back of the action, and look at the sear block on the bottom of the cocking piece. It's a rectangular block that rides between the tongs of the rail that runs the length of the bottom of the bolt assembly. The surface that matters here is the front (muzzle end) face of the block. What you're looking for is any carving or unevenness from either the trigger sear wearing on it, or someone filing on it.
Some machine marks are okay, and don't worry about some polishing from wear, but if it's showing any sort of wear groove, or it looks like some other kitchen table gunsmith has been working on it, that could be a problem.That surface should be hardened to the point that it should hardly show wear, and the angle of the face is critical for safe functioning. You probably don't want to attempt heat treatment, but a replacement cocking piece is only a few bucks. Refining the angle of the face is somewhat challenging, but definitely doable.
Once you find the Mosin-Nagant you want at the price you want, buy it and take it home. Be sure the seller includes a Mosin-Nagant bolt tool, or pick one up at the show, because every Mosin-Nagant owner should have at least one.
Cleaning Your Mosin-Nagant
Once you get your Mosin-Nagant home, the first order of business is a proper cleaning.
I don't know why so many people seem to think that cleaning up cosmoline is some mystical dark art. The stuff is messy, but it easily melts when met with any sort of strong solvent. Popular solvents include mineral spirits, naphtha, lacquer thinner, turpentine, kerosene, diesel fuel, and gasoline, among others.
All are extremely flammable, though some less so than others, and all give off potentially dangerous fumes and are bad for your skin and lungs, so wear rubber gloves, work in a well-ventilated area, preferably outside, and keep away from sparks or flames.
These solvents are also chemically sensitive and can auto-combust, especially when rags are left bunched up in a tight space, or rags with different solvents are mixed together, so it's best to pick one solvent and stick with it, rather than using different ones that could react badly.
There are cleaners and degreasers that are nontoxic and nonvolatile such as Simple Green and Dawn dishwashing liquid. These products will work, but they require more elbow grease, shouldn't be employed until as much cosmoline as possible has been manually wiped from the Mosin-Nagant and should be followed with a wipe down using a little of the stronger stuff, just to be sure the cosmoline is all gone.
Methods using water should also be followed up with a good hose-down of WD-40 to be sure all of the water is gone and the metal is protected with a light coat of oil. A light gun oil should also be applied after cleaning with solvents, because the metal is much more susceptible to rust after cleaning and degreasing.
I prefer mineral spirits and paper towels for most of the wiping, washing and soaking. It's not the strongest solvent, but it's safe for the wood and finish, it's less volatile, and I don't think it stinks as bad as others. It also doesn't dissolve plastic like some of the rougher stuff can, so I can use Tupperware bowls.
Once a towel is worn out, I just shake it out and toss it on the ground in the back yard to air out, then throw them in my old barbecue grill, away from the house, until trash day, when I just toss them in the can. The solvents in your bowls and buckets can be reused many times, just be sure they are stored in a good airtight container in a safe place.
Some contaminants will separate out into layers that can be skimmed or poured off, and you can strain it through cheesecloth, paper towel, or a paint filter to get out any dirt and chunks.
Start with a thorough wipe down with a rag or paper towel wet with solvent. Most won't hurt the finish on the stock, but if you're worried about it, test in an inconspicuous place before going any farther. Wipe off any thick or caked on cosmoline, then go over it again with a clean, solvent-soaked rag to get it looking nice. Next you'll need to disassemble the whole Mosin-Nagant and clean every part.
Mosin-Nagant Disassembly: Lock, Stock, and Barrel
Pour a couple of inches of mineral spirits in a bucket or bowl. I like those plastic shoebox size containers, but anything will work. Open the bolt and hold the trigger down to slide the bolt on out of the action. Drop that in your bucket of mineral spirits to soak while you take the rest of the Mosin-Nagant apart.
To remove the barreled action from the stock, first depress the little spring retainers and slide the barrel bands up toward the front sight. This process can require three hands, but some gentle persuasion from a wide, blunt-bladed screwdriver helps a lot.
Use a brass punch or the corner of a screwdriver handle if you're worried about mars or scratches, and be careful sliding the bands, because they can scrape the finish right off the stock. The bands won't normally fit over the front sight, so they will remain on the barrel after you remove the stock.
With the barrel bands out of the way, the top handguard is easily removed to expose the next sloppy layer of cosmoline. Now remove the two screws from the action, one on the bottom in front of the magazine and one on top on the tang at the back of the action. With the screws out and safely stowed in the bucket of mineral spirits, the barreled Mosin-Nagant action should lift out of the stock, and the trigger guard and magazine can be removed and tossed in the solvent.
Before you do anything else, look at the trigger and locate its pivot pin. This pin is probably only being held in with cosmoline, so you should go ahead and knock it out before it falls out and gets lost. Toss it in the bucket. The trigger will remain trapped by the sear spring.
Wipe down the barrel and action to get the bulk of the cosmoline off, and run a solvent-soaked patch down the bore. Wipe down the stock and set it somewhere in the sunshine to warm it up a bit while you focus on the steel parts. The warmth will help soften the cosmoline and leach it out of the wood. Give it a good wipe-down every now and then throughout the day and you'll get more cosmoline out each time.
Looking at the bottom of the action again, remove the screw holding the sear spring and trigger. You'll see that the sear spring actually becomes the sear, and serves as the trigger return spring as well. The top of the trigger rides between the sear spring and the action. Pay attention to how the trigger and sear spring come apart. It's easy to put it all back together, but it's easier if you watch how it comes apart.
Once removed, drop these small pieces into the bowl of solvent with the bolt to be dealt with later. Remove the other hardware on the action, paying attention to what goes where, there are a couple of different styles of ejector/interrupters, but either way, it's just one screw. Throw it all in the solvent. Right now we want to focus on cleaning the stripped barreled action.
It's helpful to have a bucket big enough to submerge the whole Mosin-Nagant action into, but that's not critical. You just want to have a way to keep your work good and wet with fresh solvent while you scrub and swab it. If you really want to soak it, a capped length of 2-inch PVC pipe works well, and doesn't require gallons of solvent.
The cosmoline can be pretty resistant to cleaning, especially if the Mosin-Nagant has been fired with cosmoline still in it. Start with the outside, then the bore, then the chamber. Swab out the barrel several times with a good-and-wet .30 cal. brush, then plug the muzzle to keep solvent from running out while you're working on the action and chamber.
Use a nylon toothbrush and plenty of solvent to scrub the Mosin-Nagant action, then wet a 20 gauge bore brush and scrub up into the chamber. Follow that with a .410 gauge swab. Chucking the brush and swab up in a cordless drill can speed the process up, but don't get carried away.
Once you have the chamber good and clean, wipe down the whole thing one more time and run another patch or two through the bore, then give everything a good wipe down with your light oil and set it aside.
A toothbrush and your solvent will make quick work of the trigger and sear. Just give them a good scrubbing, wipe them off, and coat them with light oil. Set these aside for closer inspection in a few minutes. I use a metal tin sitting on an old radio speaker magnet to keep track of my small parts. Now shift your attention to the bolt.
Into the Mosin-Nagant Bolt
The Mosin-Nagant bolt is comprised of four main parts: the head, the body, the cocking piece/striker and a railed guide that runs along the bottom called the bolt connector. You need to separate these parts to get everything good and clean. As removed from the gun, the bolt is cocked, so the first order of business is to de-cock it.
Begin by grasping the bolt handle in your right hand as if it were the grip of a pistol with your index finger laying against the side of the bolt. Grasp the knurled cocking knob, pulling back slightly as you rotate the knob counterclockwise and let the spring tension pull it forward.
Now the head at the front of the bolt can be pulled forward about a quarter inch and rotated counterclockwise. At this point the head and the guide can slide forward and separate from the assembly, exposing a good bit of the firing pin.
Final disassembly of the Mosin-Nagant bolt involves unscrewing the firing pin from the cocking knob. As you look at this knob, you will see what looks like a recessed standard head screw in the center of the knob. This is actually the back end of the firing pin which is threaded and screwed into the knob.
The firing pin protrusion — how far the point extends beyond the bolt face when fired — can be adjusted by screwing the firing pin in or out of this knob. The slotted head of the firing pin should be ground flush with the face of the knob and there should be witness marks scratched into the knob face in line with the screw slot to indicate where the protrusion depth was set by the last armorer to inspect the gun.
While you can use a small wrench or a Mosin-Nagant bolt tool to unscrew the firing pin, the easier way to disassemble this part of the bolt is to again grasp the bolt handle like a pistol, but this time press the front of the firing pin into a piece of wood on your bench, compressing the striker spring to the point that the whole tail assembly can be turned counterclockwise.
If the knob doesn't readily unscrew from the firing pin, use a wrench or bolt tool on the flat sides of the firing pin to unscrew it a turn or two to break the threads loose, then try again using the pistol grip technique. The tail assembly should screw right off. Remove the firing pin and the striker spring and finish cleaning the bolt components, then give them a light coat of oil.
Finish up cleaning any of the small parts still in your bucket. Be sure to get inside the magazine well and clean the spring and follower. Pressing the button on the bottom of the magazine lets the spring and follower swing out, then by squeezing the follower down against the magazine baseplate, you can slide that whole assembly off of its pivot pin.
That completes the metal parts, unless you want to remove the barrel band retainer clips, sling slot guards — or in some cases swivels, recoil lug and butt plate from the stock. Unless it's cracked or you're planning to refinish it, this isn't really necessary. The stock will clean up just fine with all of that still in place.
Most solvents won't touch the standard Mosin-Nagant shellac finish, but if you're concerned about it and want to maintain the gun's original finish, it's a good idea to do some testing in an inconspicuous spot like the interior of the handguards or the areas around the sling slots.
Once you're satisfied that your solvent of choice isn't going to harm the finish, go ahead and apply it liberally to melt and draw out the cosmoline and years of oil and grease that have soaked into the wood. There's normally no harm in completely soaking the wood in mineral spirits or similar solvents.
If you're planning to glass bed the action or do any repairs using resins like Brownells Acraglass, you want to get the contact surfaces as clean and oil free as possible so the resins or glues have a good surface to bond with. Calcium carbonate, the same stuff antacids are made from, can help to draw out oils.
Brownells sells it in a form called "whiting" specifically for this purpose, and plain old baking soda works pretty well too. No matter what you use or how much time and effort you put into it, you're probably never going to get all of the oil and cosmoline out of the wood. It's not a huge problem, but the more you get out, the less it will sweat when it gets warm.
If you're not interested in maintaining original appearance, you can refinish the original stock or you can pick up an aftermarket synthetic stock, such as the futuristic Archangel tactical stock or the classic look of ATI's Monte Carlo. There are also add-ons for the guns such as a polymer pistol grip or a rubber butt pad that will increase the length of pull.
If you're keeping the wood stock, and you're not planning to use any glue or resin, a light coat of wood conditioner — even just furniture polish — is a good idea. Reassembly is just the reverse of the disassembly process. Once you've got it all back together, make sure everything has a light coat of oil, and you're almost ready to go shooting.
Before you do though, be sure you've verified headspace and run it through a few dry cycles to function check it. Never use live ammo for function checking. Make yourself some dummies if you think you really need them, or just wait and test feeding and extraction when you've got it safely on the bench at the range.
Most good gun shops will gladly check headspace and give your Mosin-Nagant a quick safety inspection at no charge, but good manners dictate that you at least buy a box of ammo or some targets from those nice folks.
Go Shoot Your Mosin-Nagant
Now get out to the range and put it on paper. If it groups nicely and you're happy, that's all you need to do. Be sure and save your best targets though. You'll want to compare them with the targets you shoot after you make any improvements.
Also, be sure you clean the Mosin-Nagant well after shooting, especially if you're using surplus ammo. A lot of that stuff is highly corrosive and will destroy your rifle in short order if you don't get it cleaned out. Windex or another cleaner with ammonia does a great job of neutralizing the caustic chemicals, and of course that needs to be followed with your regular bore solvent and a good gun oil.
That's it for now. Until next time, shoot safe and invite your non-shooting friends to go out with you. Guns are an addiction worth sharing.