Copper buildup in Mosin Nagant rifles

BCRider

BCRider

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Hi all, thought I'd share my cleaning task experience from today.

I've shot my newer '39 Tula a couple of times now with a total of around 30 rounds down the barrel. Up to now I've cleaned it with some Windex to remove the corrosive and water soluble salts and then some Ed's Red to remove the moisture and leave a light protective oil film following the final dry patch.

Today I shot it for the third time out and since someone had given me a big bottle of Hoppes #9 I opted to use this instead of my usual Ed's mix. I was a bit shocked at the amount of blue found on the Hoppes patches and I've been working it with wait times to soak it for much of the afternoon while I putter around with other things. After some half dozen passes and letting a wet patch sit in the bore with the Hoppes the patches are still coming out with a healthy amount of blue on them.

I'm going to keep going with this until the patches come out with no blue tint but I'm frankly amazed at how much copper there is in there from only my 30'ish rounds of surplus ammo. I suspect that much of this is from "the previous owners".... Namely the Russian Army... :D I don't know what they used for a cleaning solvent but it would appear that it didn't do much for copper buildup.

The last time out I shot it from bag rests at 75 yards. I was getting roughly 4 inch groups at that distance. Which considering the plain iron sights and the rather questionable vision of the guy running the trigger seemed not too bad. It will be interesting to see what happens when the copper is finally all gone.

Now to the question. Am I the only one that found this much copper buildup in their Mosin barrels?
 
Mosin Barrel Copper Build Up

BCRider said:
Now to the question. Am I the only one that found this much copper buildup in their Mosin barrels?
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In 1997 I bought an all matching Hungarian sniper 91/30 at the Ancaster gunshow. I used 7.62 Sweets and at least 30 cotton patches to remove the copper build up even though the barrel looked new. They just kept coming out a rich dark blue but after several hours I got the last of it out.
 
Various militaries didn't do all that much to remove bullet jacket fouling, but at least the Brits/Cdns and the Americans identified the problem and dealt with it to some extent.

A lot of MILSURP barrels show quite a build up of copper fouling which can be reduced with either a de-coppering agent like Butches Bore Shine, Sweets 7.62 and Hoppes Benchrest or by using friction/abrasion with JB Paste. Generally accuracy will improve after copper fouling is eliminated or reduced.
 
My Finned M91 Mosin and especially M95 Steyr came with very large doses of copper in the barrels.
Others weren't so bad and Gras was just pristine(I wish all were like that).
 
Well, over the past 4 hours or so I've been wetting the barrel with Hoppes Copper Solvent (an older bottle of it was in the box with the regular #9 solvent and some other goodies) and dry patching and re-wetting to soak for another 20 minutes. They are coming out somewhat cleaner but I've still got a ways to go. If it doesn't clean up by tomorrow I'll go invest in one of the serious copper solvents.

It'll be interesting to see how it groups following this mega cleaning. Or if it's simply a case of my eyes and plain iron sights being limited to around 4 inches at 75 yards.
 
BCRider said:
Well, over the past 4 hours or so I've been wetting the barrel with Hoppes Copper Solvent (an older bottle of it was in the box with the regular #9 solvent and some other goodies) and dry patching and re-wetting to soak for another 20 minutes. They are coming out somewhat cleaner but I've still got a ways to go. If it doesn't clean up by tomorrow I'll go invest in one of the serious copper solvents.

It'll be interesting to see how it groups following this mega cleaning. Or if it's simply a case of my eyes and plain iron sights being limited to around 4 inches at 75 yards.
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I have a had very good luck with "Wipe-Out" brushless bore cleaner,..believe me it will take out copper fouling,..i had a 03a3 Springfield and a P-14,..the junk that came out of both those rifles bores ...!
 
Dark Alley Dan said:
x2 on Wipe Out - magic stuff. be sure to let her drain muzzle down into a container you don't ever want to see again. You'll end up with stuff that looks like grape Kool-Aid.
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Also, be careful not to get any bore cleaner on your stock or handguards,..will remove the BLO finish,..a little goes a long way,..will foam out of the chamber and all over where you don't need or want it..:)
 
One thing to keep in mind is the smoothness, or lack there of in some of these older barrels. I doubt the barrel making techniques of those days were putting out bores like modern rifles.

Not sure of your barrel condiion, but my M44 shows some signs of being shot with lots of corrosive, and that minor frosting/pitting while hardly noticeable and still a shiny bore makes a big difference.
 
x westie said:
I have a had very good luck with "Wipe-Out" brushless bore cleaner,..believe me it will take out copper fouling,..i had a 03a3 Springfield and a P-14,..the junk that came out of both those rifles bores ...!
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Used this one my K98 this past weekend. The rifle wouldn't group at all before, I thought the bore was finished. What a difference after cleaning with Wipe-Out, it now groups great. This is great stuff.
 
Kroil is a penetrating oil. I'm guessing that it is somewhat miscible with the ammonia so the mix would be a sort of milky looking suspension similar to some cutting oils that can be mixed with water.

Well, the one is done. It took a while but the last wet patch and sit did the job. At least as well as I'm going to bother with. I'm working on the second one now. It looks like it's about as bad as the first.

Since it's midnight now I think I'll just wait and get some Wipe Out tomorrow.
 
Be VERY careful with anything containing Ammonia.

Ammonia dopes can be unpredictable; the Americans used it for years and years, replaced untold thousands of rotted-out barrels from the stuff. It's all in Hatcher.

Sweet's 762 is about as strong as you can go with any Ammonia-containing cleaner for a rifled barrel.
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There are several commercially available bore cleaners that remove copper fouling, and they all seem to work. Many of my Milsurp acquisitions will require a one time solvent/treatment, but rarely need a second application if you use a good brush and proper cleaning habits, IMO.
 
smiley1 said:
Kroil? what is it and where do you find it?
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Kroil, like previously mentioned, is a penatrating oil. It's red in colour and looks like ATF. When mixed with ammonia the colour and viscosity doesn't really change.

This mix was show to me by a military arms manufacturer.
 
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When I bring home a milsurp I wet the barrel with a solvent (Hoppes Copper cutter or Sweets) and leave it over night, muzzle down on a pad of paper towels. Then i wipe out the barrel and repeat another night, until the pad does not show a dirty blotch of crap.

This might take a week. I find the over night action is substantially more than just wiping in and out.
 
Here is a little primer on bore cleaning from my blog
http://riflechair.########.ca/2010/07/managing-copper-fouling.html
 
Folks should not use a bronze brush with a de-coppering agent as the agent will attack the copper in the brush and cause it to disintegrate. The de-coppering solution is best applied with successive clean bore patches.

A bore brush is best used to loosen powder fouling and miscellaneous crud from a bore.

I like to use JB Paste in connection with a de-coppering agent. The JB paste has a mild abrasive embedded in oil and serves to slick up and lap the bore to some degree in addition to removing fouling.

Some folks like to use Kroil as they believe that it will assist the copper removal process. I use Kroil as a penetrating oil and find it No 1 for that purpose. I've tried it as a bore cleaner, but can't say that I saw much effect.
 
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