View Full Version : Joining the Mosin contingent (need grease cleaning tips!)

June 11, 2011, 05:27 PM
I ran across a Mosin 91/30 today and finally caved in. I've read dozens of threads on how much fun these guys can be, so I bought it and some Wolf non-corrosive ammo.
The thing looks like it was literally dipped in a big vat of grease, so I have some cleaning ahead of me. The guy at the shop said to just use Hoppe's solvent on the whole thing, wood and all. I'm a little skeptical about that, anyone have any experience with that? Is it OK, or should I use something else on the wood?

Looking forward to shooting this beast!

chris in va
June 11, 2011, 05:35 PM
I had an SKS that came with two pounds of cosmo. Boiled the smaller parts in water, then steam cleaned the rest. Don't boil anything in cookware you plan to eat out of later.

June 11, 2011, 05:37 PM
I just wiped off all the oil with a rag.
Then I went over it with some hoppe's.
As for the wood. Some pledge did the job for me.
It took me about 2 hours to get it clean.

June 11, 2011, 05:47 PM
I know someone who bought a Mosin-Nagant 91/30 and a new steam cleaner in the same week...:D

June 11, 2011, 06:13 PM
The last one I bought apparently had been there awhile because all the cosmoline was covered in dust. It took me about 4hrs using hoppes and remoil to get it clean. Good luck.

June 11, 2011, 06:19 PM
I bought an under-the-bed plastic tote from Walmart. It was just long enough for the barreled action fit diagonally.

Disassembled the rifle and put all the metal bits in the tote. Poured in enough diesel to cover, snapped a lid on and waited a couple-three days. Most of the cosmo dissolved on its own and a toothbrush took care of the rest.

Wiped the wood with a rag dampened with HOT water & some simple green.

June 11, 2011, 07:20 PM
It was dipped in a big vat of grease, or more accurately, cosmoline. That's why after around fifty years in storage somewhere in the Ukraine, your Mosin has no rust on it.

Completely disassemble it, and clean every part with mineral spirits and some good stiff bristle brushes... even the stock. Turp didn't hurt the varnish on my stocks. Brush and swab the bore with good ol' Hoppes #9. Finally, coat every part with some oil, and your good to go.

June 11, 2011, 07:27 PM
Cool, thanks for the tips. I have it all disassembled now. Looks like everything is in good condition, just needs a solid cleaning.
Thanks to info from http://7.62x54r.net/ I was able to find that it was manufactured in 1941 by Izhevsk (Soviet Union). Lucky me, the numbers all match on the bolt, barrel, magazine floorplate and buttplate.
I am suspicious that the stock was replaced or refurbished at some point, but not sure. Still researching.
Not that I'm treating it like a numbers-matching '73 Trans Am SD455.... ;) This gun's going to get used!

June 11, 2011, 09:07 PM
I suggest getting yourself a small can of xylene. This stuff will very quickly and efficiently remove cosmoline. With a toothbrush, and an old paintbrush I fully cleaned my Finn M39 from all the cosmoline in 15-20 minutes. I also used it to rub down the stock. For the stock I also used a heat gun to get out all the absorbed cosmo.

After the xylene/heat gun treatment I cleaned the gun as I would after shooting. If you want to really make the stock look good wipe it down with Ballistol.

June 11, 2011, 09:16 PM
If it was refurbished there is a mark on the stock saying so.

It's a little square with a slash mark going diagonally through it.


G-man 26
June 11, 2011, 09:53 PM
No joke on the steam thing. At least with the metal parts. I used a hot pressure washer, 4gpm at around 1500psi running about 150deg. Took all of 10 minuets. Rubbed down the still hot parts in Penzoil, cleaned off the excess with rags/compressed air, and cleaned the bore. Works like a charm.

Have fun with the new toy. Now you need a m-44, and a m-38.

June 11, 2011, 11:15 PM
Bingo on the refurbished stock. It has that mark on it. Thanks capflyboy05!

June 11, 2011, 11:21 PM
Just sharing the knowledge I DO have... lol.

June 11, 2011, 11:49 PM
On a Yugo Mauser I boiled the bolt and used oven cleaner on the wood...Can't remember how I cleaned the rest of the metal.

June 12, 2011, 01:19 PM
The only things likely to be original on an arsenal refurb Mosin are the barrel and receiver.

June 12, 2011, 09:07 PM
Cosmoline is a wax and not a grease. When it is applied, it is done in a tank that contains hot cosmoline. There isnt a much better preservative for metal and that is why it is used. Because it is applied hot, the cosmoline is water thin when applied and soaks into wood readily.

This makes its removal a bit difficult, but the best chemicals to remove it are wax removers. What I use to remove it is not recommended because of the safety issue, but it seems to work better than anything else I have tried.

I wear surgeons gloves and mask, safety goggles, and a rubber bib. This is done outside and away from any heat source or spark. I do NOT use this chemical on wood because it can easily soak into the wood and become volitile. Once the parts have been cleaned, they are rinsed off with safety solvent along with brushes and rags. Rags are then hung on a line to dry (this substance is well known to cause spontanious combustion with cloth if left bundled up).

the rifleer
June 12, 2011, 09:29 PM
Heat. Boiling the parts works, but for the bigger parts so does just getting them hot. Cosmoline melts at like 120-40 degrees I think, you just get it about that hot.

June 12, 2011, 09:50 PM
I jut use Hoppe's #9, rags, and a toothbrush.

June 12, 2011, 10:36 PM
Mine is refurbished.
But everything has the exact same serial number.
Not etched either. :)

Willie D
June 12, 2011, 10:58 PM
Steam or soaking in Mineral Spirits are the best; Simple Green works well with a little elbow grease and won't poison you either.

June 13, 2011, 12:29 PM
She is coming along nicely. All the metal parts have been thoroughly cleaned. The chamber and barrel are nice and shiny. I will steam the stock tonight.
Next I plan to slug the barrel and get the headspace checked. I plan on hand loading for this one as well.
This has been very enjoyable for me. I've never in the past had a gun that needed much attention beyond basic maintenance and I am finding I really am enjoying tinkering with this one.
Will upload pics tonight.

Sent via Tapatalk ~Android~

June 13, 2011, 08:35 PM
If you have a Mosin arsenal refurb, even one of the nicer ones with neatly stamped matching numbers and Cyrillic letters on the bolt mag floorplate, and butt plate, look closely at those numbers. You'll likely find that the size, or the font, or the basic shape of those numbers do not match those on the barrel. The odds are overwhelming that all those parts were force matched.

June 13, 2011, 09:21 PM
No biggie! Long as she shoots I'm happy. Don't expect much from a $99 gun.

Still working on getting all the cosmo out of the wood. Not sure it's worth that much trouble... though I am considering sanding down and refinishing the stock.

Sgt Pepper
June 13, 2011, 11:08 PM
Aerosol brake parts cleaner is what I have used with excellent effectiveness on cosmoline. The spray helps wash off and get into the corners and crevices, and evaporates quickly. No residue and no harm to the parts. Does a very quick job and is cheap, too.

Heat will bring the cosmo out of the wood and any other place that you did not or could not reach. Just shooting the gun a bunch may bring some to the surface. Just wipe as you go.

June 14, 2011, 07:28 AM
My standard cosmoline cleanup consists of TSP (a cleanser found in hardware stores) in hotwater followed by BLO (boiled linseed oil).