Copper fouling a good thing?

Pheroze

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I was reading up on cleaning and I came across this video by "Gunblue490". What struck me was his statement that copper fouling is actually beneficial and not to remove it with copper solvents. I had thought that copper buildup was bad. I understood that the biggest complaint against the Barnes bullets is the copper buildup but this fellow would seem to infer that this concern is misguided. Gunblue490 seems to indicate that after an initial buildup the copper will smooth out the bore preventing further problems including further copper buildup. I was wondering what you folks think of this?


 
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I cleaned one of my barrels of all copper using an Electrolytic process. It was down to the bare steel.

I went out to shoot some targets, expecting some amazing improvement with this clean barrel.

I got the exact opposite result.
The worst groups the rifle ever shot. (My shotgun pattern looked better.)

After shooting about 30 rounds through the barrel, I had excellent groups again.

I'll clean this rifle, but it will never have all the copper removed ever again.
 
Depends on the gun, one gun I got rid of only shot well with a dirty barrel. Most of my guns shoot well with a clean or dirty barrel.
 
Yeah, all of the above. I have a M70 in .300WM that hates a super clean barrel, takes at least 6 shots exhibiting blind man accuracy and then it suddenly pops back to normal. My son's Tikka .308 couldn't care less if the barrel is clean or dirty, always accurate. My M70 .375 virtually the same story.

That said, I've seen the copper fouling issue with the Barnes bullets in some of my rifles. They're good for awhile, but then when it goes it goes quickly.

I think the thought on now scrubbing the barrel down to the steel is to use the copper to your advantage to act as a barrier between the bullet and the steel and thus save barrel life.
 
I like to take all the copper out, knowing it may take a few rounds before it settles in again. Too much copper over time might actually shrink bore size a tad, though probably not enough to hurt anything. My dads old Win .284 had NEVER had its copper cleaned out before and it took quite some time and lots of elbow grease to get it down to bare metal, but accuracy did improve after that. In the old days, no one bothered with such things. A few wet patches with the old #9, dry it, oil it, done.
 
the copper in the barrel of ANY rifled gun is a BAD thing.... Sorry, i´m new in the forum, but old in gunsmitting ...
The copper, because your chemical composition and electronic number cause an electrolitic caustic effect to the steel of the barrel!
This process is known as erosion... because of this, I´m clean the barrel completely after every hunting day or shooting practice! I never saw the small ammount of copper improves the precision, instead...
Beside that, te accumulation of major ammounts of copper causes overpressure, deformations of the cannon and brake the bore...
 
just saw my typo in the first post...ugh

anyway, I found this video interesting because in the copper fouling debate I had not heard that the copper fills in the imperfections in the bore leading to better accuracy. I also find that there is alot of comment against Barnes for the copper fouling but none against Swift A-Frame which has a pure copper jacket. So it made me wonder about the whole debate.
 
Barnes are a very good bullet! If the copper is a fail in te design... I don´t know... but... are any way to unuse the copper?...MMMMMMMMMM.... i thik NOT...
debate or not debate... TO BE OR NOT TO BE... it´s a good bullet instead...
 
If it ain't broke, don't fix it...

If a rifle starts to lose accuracy then it may be time to clean the copper out, but until then I just get all of the carbon out. I had two Navy Seals and a USMC Sniper tell me they only removed copper very infrequently. Good enough for me!

As others have said, take all of the copper out and it may take a few rounds to get the rifle grouping again.
 
I am good for it! Although, I will be more careful when I am trying to sneak a post in between meetings at work!
 
the copper in the barrel of ANY rifled gun is a BAD thing.... Sorry, i´m new in the forum, but old in gunsmitting ...
The copper, because your chemical composition and electronic number cause an electrolitic caustic effect to the steel of the barrel!
This process is known as erosion... because of this, I´m clean the barrel completely after every hunting day or shooting practice! I never saw the small ammount of copper improves the precision, instead...
Beside that, te accumulation of major ammounts of copper causes overpressure, deformations of the cannon and brake the bore...

The process that you mentioned I believe is known as galvanic corrosion which takes place when two dissimilar metals are in contact with one another. You have a valid point, but I'm not sure which is worse. The passing of a bullet across the bare steel or the corrosion effect of having the copper in contact with steel?

My guess is if your rifle is used on a regular basis it better to leave the some copper in place. If the rifle sits for long periods of time between use, then cleaning thoroughly would be better.
 
the copper in the barrel of ANY rifled gun is a BAD thing.... Sorry, i´m new in the forum, but old in gunsmitting ...
The copper, because your chemical composition and electronic number cause an electrolitic caustic effect to the steel of the barrel!
This process is known as erosion... because of this, I´m clean the barrel completely after every hunting day or shooting practice! I never saw the small ammount of copper improves the precision, instead...
Beside that, te accumulation of major ammounts of copper causes overpressure, deformations of the cannon and brake the bore...

+1 on what Marcos said (even though I freely admit that I am not a Gunsmith).
I used to be a welder though (early 1970s) and in the basic classes, we learned that when steel is pressed tightly together with dissimilar metals, for long periods of time, it will often rust.

Furthermore, most of my rifles shoot tighter groups with the fouling removed from the riflings.
The odd ones I have had that shot better with a slightly dirty bore did so with no more than one or two fouling shots.
None of my rifles, past or present, have shot well with excess fouling in them from firing many shots between cleanings.
 
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Don't know that this applies as a blanket statement as every barrel is a unique "individual", but here's one experience I have had that might have some value.
In developing handloads for a .300 WSM I was coming to the conclusion that the gun didn't like Swift Bullets. What I learned through continued testing and development was that it didn't like the pure copper from those bullets laid down OVER the dissimilar copper of the Hornady or Sierra bullets. When I cleaned the bore down to bare metal and then fowled the bore from the get go with Swifts they seemed to shoot very well. Over the top of something else, no bueno. Looking at the bore with a bore scope, the copper had kind of a clumpy look with irregular distribution. After that I try not to mix Barnes and Swifts with other bullets in the same gun. This was in a stainless barrel.
Overall I'm a believer in best accuracy with some copper in the bore. Not only best accuracy, but most consistent and predictable first round shot placement with a fowled bore vs a clean bore. Just my 2 bits :D
 
Also agree with Velo Dog, excess fowling is never a good thing.
 
Barrels can be very different.

Some needs a bit of fouling, others not at all.
Some are very smooth and gets hardly any fouling at all.
Others needs a cleaning after few shots as it fouls very quickly.

And they can all very very accurate when they get the situation they need.
And some seems to not care much about what they get, they are either always accurate or never accurate at all.

I owned a 9.3x62 Mauser with a S&L barrel that was very finicky.
It always needed 2-3 fouling shots and then it was very accurate( 1/2 moa 3 shot groups) for 20-25 more shots and then the accuracy deteriorated quickly.
I hate gun cleaning, so I sold it to a friend that likes to clean his guns.

My 6.5-06 with a Shilen stainless steel barrel is very smooth and hardly needs any cleaning at all.
I have had it for 22 years now and I think I have cleaned it 3 times in that time and shot around 3500-4000 shots with it.
And it shoots sub 1/2 moa 3 shot groups with my best loads, 1 moa groups with almost whatever I feed it with and most loads hit the same spot at 100 meters.
My 80 gr Norma FMJ RN, 85 gr Sierra Varmint, 100 gr Sierra Varmint, 120 gr Swift A-frame and 120 gr TTSX loads make a sub 1" group at 100 meters.

My Tikka M65 in 6.5x55 is also very accurate and doesn't need much cleaning.
I don't know how many thousands of shots that have gone through the barrel as I bought it used and the previous owner had used it for competition shooting.
I don't know if he ever cleaned the gun as the barrel was extremely fouled when I bought it.
But when I finally got it totally clean, it shot very well.
I have still not cleaned it again after that first time and even after minimum 1000 more shots, it still is very accurate.

I have managed to ruin one barrel because of lack of cleaning.
Or to be correct. Because of lack of getting the barrel dry and leaving the silencer on.
I had been out hunting with my 223 Remington 7 with a silencer in very bad weather conditions and shot a deer.
When I came home, I had to rush off and had no time to clean the gun and just put it in the gun safe and totally forgot about removing the silencer because of the stress.
Of course I managed to totally forget about the gun in the safe for some months:oops:, even if I took other guns from the safe and hunted with them.
When I took the gun to the shooting range, I had 10" groups at 100 meter if I was lucky:confused:
The barrel was totally ruined with one of the sides in the barrel at the muzzle being almost like a smooth bore:cry:
I felt like a total idiot then:mad:

It has not made me clean my guns more, but I make very sure to take the silencer off of the guns that have them when I come home from a hunt.
 
Phil, you´re RIGHT.... galvanic corrossion... sorry about my english!...
It´s a fact... there is not a barrell equal to another barrel!... but in the most of cases, the clean thorougly.... pays!
The barrel of my "obsolete"... the mauser 7,65x54, is carefully cleaed after any fire session or hunting party, and because I live in the coutry, ther means two or three times a week... Also, i impregned the barrel with molybdene disulphure... GREAT THING TO DO....
 
All my rifled barrels get scrubbed totally clean with the "Bore-Tech Eliminator", then treated with a light oil for storage.
All my barrels are "run in" using the same process any serious bench rest competition shooter does. This seems to give the barrel a "memory"? It only takes 3 or 4 patches of Eliminator for it to be clean again. Doesn't matter whether it's a stainless or chrome moly build.

Shooting competition I notice a steady decline in accuracy with more shots fired. The number of shots fired vs group opening up depends on caliber and velocity( or rather intensity). For example- My 6x45 takes over 50 rounds of firing before it starts to shoot higher. My 8mm Rem Mag can only afford 15 shots without cleaning before groups open up, same can be said with the 416 Rem Mag with hot 300gn loads.

A build up of copper fouling on the lands also causes all sorts of drama with powder fouling. It seems to create a surface area which traps the powder fouling and retains it. With the next shot it quickly turns to carbon and imparts more deformation on the projectile than what the rifling would. Hence the decrease in accuracy.

All my firearms are worth too much not to take the time and ensure the bores are clean before shooting. Cleaned and lightly oiled for storage.
 
My Tikka T3 with Barnes tipped TSX bullets has to be cleaned often. Use the bore tech and its good for 10-15 shots at 1/2 min. Get to 20 down the barrel and its 2 inches at 100 yards. I have other rifles that go 100 plus rounds and are still accurate. Depends on the barrel and the bullets being used. Bruce
 
If I must share a comment here, firstly during hunting season i only clean my barrels with good old Hopes No .9 and after hunting season I remove all the copper out of the barrels with a proper copper cutter and then i run a patch through all my barrels so as to leave a thin layer of oil in the barrels as a conditioner just to protect against corrosion.

If I remove all the copper during hunting season, I notice that my group open up quiet a bit, so I have stuck to the method above and never had a problem
 

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