Excessive copper in bore?

andyo5

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I have a S&W M&P MOE model with a 16" barrel. I am shooting Hornaday 55g bullets at around 3000 fpm. For some reason, I seem to get alot of copper fouling, more than I would expect for a fairly new rifle that has never shot corrosive ammunition (see photo). The photo shows the 6th patch to come out of the bore after wetting with solvent. The prior patches had even more blue color than this. Solvents are Shooter's Choice MC-5, and Hoppe's #9. The patch in the photo shows the result with Hoppe's, after several hours of soaking. I had shot less than 100 rounds since the prior cleaning. I have never used an ammonia based cleaner in this barrel.

My question: Does this seem excessive to you, or does it match your own experience with M&P ARs.
Thanks!
 

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Regular Hoppe's #9 is good bore cleaner, but really won't remove much, if any, copper fouling. I'm unfamiliar with MP-5, but from the color of your patches, your getting some copper removal either from the bore, brass cleaning tips and / or brushes, or both.

Cleaners with ammonia work, but there are other copper removers without ammonia that will do at least as well and don't have the ammonia fumes, like Wipe-Out/ Patch-Out, the best I've found so far.

It's not necessary to remove the last trace of copper in a bore for the bore to shoot well. You just don't want to have an excessive amount of carbon buildup because that can adversely affect accuracy. It will take some trial and error as to how much removal is adequate with a particular bore. Rough bores foul worse and much quicker than bores that are smoother.

I do preliminary cleaning with something like regular Hoppe's #9 and then brush to get most everything in the bore clean. Then I apply a copper solvent, if necessary, let it soak for a while and do no further brushing.
 
Not unusual, I am sure there is plenty of copper left in the bore, if accuracy is acceptable to you, I wouldn't stress over it
 
Not unusual, I am sure there is plenty of copper left in the bore, if accuracy is acceptable to you, I wouldn't stress over it

It seems to collect more copper than any other rifle that I own, with the possible exception of my WWII-era K98 Mauser. My basic question is whether this is normal for an AR15, or whether I need to have S&W look at the possibility of a rough bore.
So I am asking whether AR15s tend to collect more copper than other types of rifles.
Yesterday, I reached the point where accuracy fell apart and the rifle had to be cleaned. Round count between cleanings was under 100.
 
It seems to collect more copper than any other rifle that I own, with the possible exception of my WWII-era K98 Mauser. My basic question is whether this is normal for an AR15, or whether I need to have S&W look at the possibility of a rough bore.
So I am asking whether AR15s tend to collect more copper than other types of rifles.
Yesterday, I reached the point where accuracy fell apart and the rifle had to be cleaned. Round count between cleanings was under 100.

I would say what you are seeing for a chrome lined bore is not normal, if your bore is not chrome lined then all bets are off. Maybe clean it up real good and take a peak down the bore to see if there is a bunch of machining marks, it should be nice and shiny.
 
Compared to custom barrels, if you look at the bores of mass-production factory barrels using a bore scope, many appear rough. That doesn't mean they shoot inaccurately, it just means they foul quicker, sometimes much quicker.

I only have a couple of chrome-lined barrels (AR 15 Colts) and don't recall if I ever bore-scoped either. The smoothest factory bores I've seen have been on two fairly recent production Winchester Model 70 Extreme Weather models, one in .308 and the other in .30-06. While they didn't shoot any better than many other rifles, copper fouling was minimal at best.
 
I applied Dyna-Tek Bore Bore Coat to one of my AR's a couple of years ago. The process involves cleaning the barrel down to bare steel (or chrome) using both solvents and abrasive cleaners. I thought that I would never stop getting blue patches. Turns out that AR's collect both copper fouling and solvent in the junction of the flash hider and muzzle.

The only way the OP would know whether or not he has a fouled bore or is picking up blue fouling somewhere else is to use a bore scope. Brass brushes will leave fouling in the barrel. Brass jags will leave blue on the patches if used with some solvents, particularly if not decontaminated between patches.

Don't sweat the small stuff.
 
I would say what you are seeing for a chrome lined bore is not normal, if your bore is not chrome lined then all bets are off. Maybe clean it up real good and take a peak down the bore to see if there is a bunch of machining marks, it should be nice and shiny.

The bore is not chromed lined. It is cryogenically treated, which is why I can't use an ammonia based cleaner like Sweet's.
 
Did you have the barrel treated after you purchased your rifle? Why can't you use ammonia based cleaners? I had researched this but didn't see anything on cleaning except that treatment was supposed to help cleaning. Not sure I ever read anything that proved effectiveness of freezing, lots of opinions for sure.
 
I had the same problem. I sent the gun back and they replaced the barrel. It's very accurate too. ( CORE) pistol.
 
Did you have the barrel treated after you purchased your rifle? Why can't you use ammonia based cleaners? I had researched this but didn't see anything on cleaning except that treatment was supposed to help cleaning. Not sure I ever read anything that proved effectiveness of freezing, lots of opinions for sure.

Well, I checked my owner's manual. All it says is that ammonia based or alkaline cleaners should not be used on any S&W firearm. But that's not what stopped me from using it, since I use Sweet's on my other S&W firearms. As I recall, I called S&W and spoke to someone in customer service. They advised me tht the barrel was cryo-treated and that ammonia would damage the surface.
I did not have the barrel treated after purchase.
 
Ammonia will damage about any steel if you leave it on the surface long enough. I doubt normal cleaning with an ammonia-based solution would hurt anything, but it would probably not be advisable to leave the solution in the bore for more than fifteen to thirty minutes. Not only does it need to be adequately removed from a bore, a very light but thorough coat of oil should be applied. As for cryo treatment, that shouldn't matter unless they put some sort of fragile coating over the bore after it is frozen.
 
Ammonia will damage about any steel if you leave it on the surface long enough. I doubt normal cleaning with an ammonia-based solution would hurt anything, but it would probably not be advisable to leave the solution in the bore for more than fifteen to thirty minutes. Not only does it need to be adequately removed from a bore, a very light but thorough coat of oil should be applied. As for cryo treatment, that shouldn't matter unless they put some sort of fragile coating over the bore after it is frozen.

My thoughts as well but no proof except personal experience not showing any effects on the accuracy of my rifles. I have had mil-surplus rifles that had extremely dark and pitted barrels that were still reasonably accurate and shot better as they built up copper deposits.
 
Ammonia will damage about any steel if you leave it on the surface long enough. I doubt normal cleaning with an ammonia-based solution would hurt anything, but it would probably not be advisable to leave the solution in the bore for more than fifteen to thirty minutes.

I always time how long I leave it the barrel and use 10 minutes as the maximum. I always dry the bore with a clean patch, and then use a non-ammonia solvent like Hoppe's after using Sweet's. Finally, I patch out the bore again and leave a thin coating of gun oil.

My WWII Mauser is a real copper mine. It will shoot well, but pitting from the old corrosive ammo they shot back in the day causes alot of copper to collect. Sweet's is the only solvent that will remove it.

Come to think of it, I may be confusing 'cryogenic' with 'nitriding'. The website says that the barrel is 4140 steel with Armornite treatment, which I think is nitriding.

I think I might call S&W when they reopen on the 3rd and discuss with them again just to be sure.
 
Run a soaked patch with sweets copper remover then after a few minutes a dry patch. Repeat and then rinse thoroughly with isopropanol. Then dry and a dose of ballistol to finish. Never and copper build up.
 
I'm no expert, but that seems like an awful lot of copper to me. Have you tried other ammo than the Hornady?
 
I'm no expert, but that seems like an awful lot of copper to me. Have you tried other ammo than the Hornady?

Yes. Sierra bullets, and Federal commercial ammunition. Makes no difference.
Do you get less copper out of yours? If so, what cleaner do you use?
 
I spoke with Tom in S&W customer service today. After conferring with two other technicians, he affirmed the following:

1. The amount of copper I am seeing is normal for these rifles.
2. Use of ammoniated solvents such as Sweet's will ruin the nitrided finish in the bore. This is not what I wanted to hear, but there it is.
 
I spoke with Tom in S&W customer service today. After conferring with two other technicians, he affirmed the following:

1. The amount of copper I am seeing is normal for these rifles.
2. Use of ammoniated solvents such as Sweet's will ruin the nitrided finish in the bore. This is not what I wanted to hear, but there it is.

So basically any bore cleaner with a copper dissolving component will ruin the finish on your barrel?
 
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