Hard carbon removal from surplus rifle

I have a surplus rifle that has a completely black bore. I can tell that it has strong rifling, but it looks like it has been completely covered in rhino truck bed lining. I’ve thrown all the cleaners I can think of at it over the past few months, including JB Bore Paste, and it looks a little better, but it’s still black as the inside of a barbecue grill. I’m not getting any green patches with anything, but every so often I’ll get a grey patch with a very faint pale blue/green tint to it, so there may some copper in there too. What would you guys suggest to clean this sewer pipe looking bore?

Have you tried plugging the bore and filling it with solvent overnight?

You do need something that wont attack steel if you try this.

Robert

Elbow grease, with a patch wrapped around a JB Bore inpreganated bore brush and then shoot some jacketed bullets in it until the bore is good and hot. Rinse and repeat.

Not tried filling the bore yet, but I’m all out of elbow grease, and close to out of JB Bore paste. I’m guessing that this stuff has been there since the 40s, and probably has a whole war’s worth of junk in there. I’ll look at options for a soak tomorrow.

Greetings,

I had a similar task cleaning one of GrandPa's old A3-'03 rifles.

After many strokes with Hoppes and a brass brush, I degreased the barrel and connected my Outers Foul Out with Copper electrolyte. Many hours later the bore started to come clean.

I dumped the electrolyte routinely and pushed a patch through the barrel. It came out an ugly black color until the Foul Out had cleaned all the remaining crud out.

Thinking back, this project took me quite a while to get all the Copper out.

No Foul Out? Try some Sweets. Yes, it is nasty stuff so don't get any on you.

Cheers,

Dave

I had Mosins with that barrel condition.
Mostly I filled the barrel with Ammonia and let it sit overnight.
I sometimes had to repeat that several times just to get the copper out.
For solid carbon , I used oven cleaner in a warmed up barrel.
If those didn't work,
My next step was soak the barrel in Vinegar.
That does take off the bluing.
But if it is that bad of a barrel ,I intend on totally rebuilding it anyway.
But JB bore bright works good.
It takes a long time and eventually you will wear off the sharp edges of the rifling.
But I have used JB bore bright with lapping slug on cleaning rods that I made casting the slug with JB Weld

Bore teck eliminator / wet mop and let soak re mop every 5 / 10 minuets then just let soak barrel down all copper and crud will come out won't hurt steel like sweets

Be patient with it. It took awhile for it to get that dirty. Don't get frustrated it also takes awhile to clean it all out.

I had a Garand almost that bad.
I ran a wet patch of Hoppe's #9 through it every day or so for several weeks before it looked new again.

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Originally Posted by Winger Ed.

Be patient with it. It took awhile for it to get that dirty. Don't get frustrated it also takes awhile to clean it all out.

I had a Garand almost that bad.
I ran a wet patch of Hoppe's #9 through it every day or so for several weeks before it looked new again.

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Good advice. You can’t put metal back on. I use some JB, but sparingly.

While it's slow Wipe Out is the best product I have found for removing hard carbon.

https://sharpshootr.com/wipe-out/

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Originally Posted by Winger Ed.

Be patient with it. It took awhile for it to get that dirty. Don't get frustrated it also takes awhile to clean it all out.

I had a Garand almost that bad.
I ran a wet patch of Hoppe's #9 through it every day or so for several weeks before it looked new again.

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I will say that Hoppe’s has had the greatest effect on it so far. At least now the grooves and lands are well defined. Originally it just looked like the smooth inside of a tailpipe. I was worried that it was shot out, but now I can tell that it has plenty of rifling left.

Lye works good for softening or dissolving any organic substance including carbon. I don't think it will hurt steel, but I'd experiment first for sure. Hot caustic tanks is what they use, (or at least to) to clean engine blocks and heads, and it works great. It will eat aluminum though. jd

About a year and a half ago I bought a used Ruger 1-V in 22-250 that had a barrel that sounds similar to the one you described. I also had bought an endoscope to view the bore, which was a revelation in itself.

I learned a couple of things that I never realized before the first of which was that copper solvents will NOT remove hard carbon. I tried Hoppes, Butches, Sweets and Boar Hog. They were effective at removing the copper but still left the black hard carbon fouling.

The only thing that I found that was able to remove it was Kroil and JB Bore paste, a copious amount of elbow grease and a LOT of patches.

Forrest's Foam

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Originally Posted by Mr_Flintstone

I will say that Hoppe’s has had the greatest effect on it so far.

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I really like the stuff, and buy it by the quart.
I even leave used wet patches on the bench until they dry out.
They make great air freshener.

I've had good luck using Kreen (made by Kroil) for carbon removal https://www.kroil.com/products/kreen...oil-treatment/ I learned about it on another shooting forum.

-Ron

Try Carbon off oven cleaner. I've used it many times in the past on two stroke motorcycle pistons.
https://www.amazon.com/Discovery-Pro.../dp/B0000E2VTM

If I were working on something like this I'd inspect it with a borescope to see just exactly what condition the bore really is in. A Teslong scope can be purchased very reasonably these days and if it turns out that bore is dark due to excessive corrosion then at least you'll know cleaners aren't going to do anything aside from wasting your time and money.

Many shooters do not understand the difference between copper fouling, carbon fouling, hard carbon deposits and corrosion damage. No one can look down a bore and know what it is. Looking at patches won't tell you what it is either but many refuse to accept it.

I also see posts all the time from shooters who say something along the lines of 'gunsmiths love borescopes because they sell rebarrel jobs' or something to that effect. If the firearm won't shoot a group then knowing what condition the bore is in isn't going to sell a barrel. The firearm not grouping is what sells the barrel.

If you haven't already take it to the range and shoot it. Often old mil-sup rifle barrel bores look terrible but will still shoot reasonably well. If it shoots to your satisfaction take it home, clean it as you always have and enjoy it the way it is. If it doesn't shoot well then inspect the bore for possible causes.

My 303 SMLE bore looks nasty but it shoots. I only shoot my cast boolits out of it. Was hitting a 4" plate at 1 hundred yards, with a peep sight.

M0A no, but minute of deer/ steel plate, all day long!
Now I just need to come up with the money too put the correct wood back on it, bubba got a hold of it!

I would try plugging the Bore and letting it soak in carburetor or brake cleaner. Then some heat with a heat gun( careful as these solvents are flammable)and some elbow grease. Be careful with abrasives as you can do more harm than good. Also sometimes shooting a few shots first loosens up decades old crud.

A little ED'S RED will help if used with copious amounts of elbow grease.

Use Boretech's C4 Carbon Remover. It is a liquid so easy to soak the bore in it for a while then patch it. Note that it will also remove copper, so be careful using any brass cleaning pieces.

I don't bother to scrub, just let it soak as long and as often as required to dissolve the carbon & copper.

45_Colt

remove oil, plug bore, fill with white vinegar for a few hours [ not too long, slightly acidic keep off of blued surfaces ] then use tight fitting brush - repeat if necessary -

OK. Dad put away a Win M100 308 for over 30 years thinking it was ‘shot out’. As I got older, I began readying more on smithing and building AR’s. Anyway, a good topic one night was about copper fouling in the barrel. Ah Ha! Copper stacks up in the grooves and can cause great inaccuracies and sometimes PRESSURE!

This old rifle was splattering rounds on the target. Scope, mounts, can get it to group. Pressure blew the mag out and the op rod. Uh Oh!

I spoke to a reputable barrel manufacturer and he stated this is most common to auto rifles as well as high pressure high velocity rounds. He suggested I use a foam copper bore cleaner, let it sit 15-20 minutes, brush, and dry patch until NO MORE BLUE comes out on patch. It took me 92 times/patches before the patch came out with a slight grayish color.

WOW! This rifle shoots and groups once again! Told a buddy about this and he had a 22-250 Ruger 1 that was doing the same thing. Gunsmith told him to sell it. He did the same and SAME RESULTS! He now states after about 25-30 rounds, gotta clean again and it goes right back to grouping.

I would suggest thinking about this on an old military rifle. I did this on all my rifles and amazingly the groups on each had deteriorated a bit, but returned to the ‘tightness’ of my initial reloads.

GOOD LUCK… Largest investment; TIME.

CLR also will work, it it will remove the bluing.

Just using what I have, I’ve continued to use Hoppe’s #9 and Rem 40-X with brass brushes and patches. Today I really scrubbed at it with the 40-X and an undersized brush doing many short strokes all along the length of the barrel, and followed up with about 30 full strokes with a slightly oversized brush. After patching it out, I ran my borescope through it. This is a 6.5 Carcano, and I haven’t found any 6.5 brushes locally, so the undersize brush is for .243, and the oversized is for .270.

The slow twist half of the barrel from the breech end to about half way are starting to show metal through the carbon. The closer to the muzzle, the worse the fouling. It’s especially bad right at the muzzle. There’s something there that’s not coming off. It could be copper, cupro-nickel, carbon, or possibly even a little rust, although there doesn’t appear to be any pitting. I won’t know for sure until I wear it down a little more. It does feel much smoother now when I run the cleaning rod down the barrel.

Make up a electronic bore cleaner.Lots of site with instructions on how.Amazing what will come out.

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Originally Posted by herian67

Make up a electronic bore cleaner.Lots of site with instructions on how.Amazing what will come out.

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I may just do that. I’ve actually been looking at plans over the past few days.

Here's the deal. After all that work, if it's not showing signs of cleaning up, you've probably just got a dark bore. Shoot it and don't worry about it. The ones with great barrels are usually evident right away. If it bothers you, sell it and buy one with a pristine barrel.

These guns were shot with corrosive ammo and carried through hell. They stayed wet, got filled with sand and snow, etc. The majority of the rifles that were actually fired in anger show the aftermath. By and large, the ones with perfect barrels never saw actual combat/war. They may have been carried by supply battalions, sentries, or rear guard troops, but they didn't live in the muck.

Shoot it and move on.

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Originally Posted by truckjohn

Here's the deal. After all that work, if it's not showing signs of cleaning up, you've probably just got a dark bore. Shoot it and don't worry about it. The ones with great barrels are usually evident right away. If it bothers you, sell it and buy one with a pristine barrel.

These guns were shot with corrosive ammo and carried through hell. They stayed wet, got filled with sand and snow, etc. The majority of the rifles that were actually fired in anger show the aftermath. By and large, the ones with perfect barrels never saw actual combat/war. They may have been carried by supply battalions, sentries, or rear guard troops, but they didn't live in the muck.

Shoot it and move on.

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I’m sure it is a dark bore. I would like to get as much crud out of the grooves as I can before I slug it again. I’m not sure how accurate my first slug was because the bore was so rough. It slugged at .268 the first time, and I want to make sure I get the correct size bullets or it will never shoot with any degree of accuracy.Factory ammo shoots a pattern like a shotgun, and PPU .267” bullets shoot better, but not great. I believe with the correct diameter cast I can reduce the size of my groups.

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Originally Posted by Mr_Flintstone

I’m sure it is a dark bore. I would like to get as much crud out of the grooves as I can before I slug it again. I’m not sure how accurate my first slug was because the bore was so rough. It slugged at .268 the first time, and I want to make sure I get the correct size bullets or it will never shoot with any degree of accuracy.Factory ammo shoots a pattern like a shotgun, and PPU .267” bullets shoot better, but not great. I believe with the correct diameter cast I can reduce the size of my groups.

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Ok! Now we're getting somewhere! If you stated factory ammunition makes a shotgun pattern before then I missed that. Often there will be alternating layers of carbon deposits and copper fouling. Years ago I bought a bolt action .308 that didn't group well at all. I was very inexperienced as a shooter at the time so I largely blamed myself. Read an article about copper fouling and decided to make sure the bore was actually clean. I started leaving copper solvent in it overnight and it took about 10 days before I finally stopped getting green patches out of that barrel.
That rifle shot really well after that but it would not shoot unless it was fouled. And the quickest way for that to happen turned out to be to shoot it about 5 times then let it sit overnight. Next day it would shoot very accurately. It took 15 shots or more to get it fouled enough to group on the same outing.

So not everything works every time for every rifle. Time and elbow grease are the only way to clean a neglected bore up and even then it might always shoot a shotgun pattern. If you spend a few dollars on a bore scope at least you'll know why the bore is dark. If it's corrosion damage it'll never get any better. The best you might do is polish it up eventually but it'll take many, many hours of brushing.

BTW - the copper solvent I used may or may not have been pretty weak. It's been a few decades and I don't remember what it was. Some copper solvents are said to etch the bore if they're left in the barrel more than a few minutes but I doubt it'll make any difference on a barrel like you described that you have.

4/0 steel wool wrapped around a patch has enough aggressiveness without harming the barrel.

OK. I finally got the carbon off my lands. They now appear to be a coppery brass color from end to end. The grooves appear to be filled with either nasty copper deposits or they are very pitted. The low resolution of my old cheap borescope won’t allow me to tell which. I am going to try some copper removal next to see if it cleans it up any, and if not, JB Bore paste will be my last option that I can try without buying new cleaning items. Either way, this is not ever going to be a pristine barrel.

I slugged the bore again, and I got a groove diameter of .2685” and the lands measured 2.565”, so the metal is there for the lands, but the bore is really ugly. Maybe shooting it some more will help clean it up.

+1 for making an electronic bore cleaner. Everybody has an old phone charger laying around.

That’s still on my list of things to look at.

I made an electronic bore cleaner years ago. It worked ok. I had received some Witches Brew from PAC-Nor barrels. It works great and a lot faster than waiting on the electronic cleaner.

https://www.youtube.com/watch?v=-DMCEutvhDQ

I think I'm going to try this method.

Slim