Copper fouling

[spudgun]

Couple questions.

New Barrel, 6.5 Creedmoor.

Broke the barrel in with 30 rounds. Shoot clean, shoot clean etc...

Getting great groups with my reloads.

Notice heavy copper fouling at the last 2" of the barrel.

I have cleaned with hoppe's copper remover and can get about 90% of the copper but keeps coming back.

The question I have is what is your thoughts on using a brass brush on the bore to remove the copper?

What could cause this to quickly Copper up at the end of the bore?

Load Data: 140 Gr Hornandy HPBT Match, 2670 - 2700 FPS.

 

[mongo chicago]

I have tried almost all of them awhile back. KG 12 works the best for me with Montana Extreme second. I just accept that barrels will foul and I don''t worry about it. Just do a good cleaning after shooting and get it ALL out. The more you leave in the more it will foul. Phosphorus Bronze brushes are good but I got tired of all the bristles coming off and switched to nylon.

 

[46and2]

Couple questions.

New Barrel, 6.5 Creedmoor.

Broke the barrel in with 30 rounds. Shoot clean, shoot clean etc...

Getting great groups with my reloads.

Notice heavy copper fouling at the last 2" of the barrel.

I have cleaned with hoppe's copper remover and can get about 90% of the copper but keeps coming back.

The question I have is what is your thoughts on using a brass brush on the bore to remove the copper?

What could cause this to quickly Copper up at the end of the bore?

Load Data: 140 Gr Hornandy HPBT Match, 2670 - 2700 FPS.

You could (possibly) still have a burr still in the start of the rifling. Is this a factory barrel?

Tubbs Dust could help.

 

[rwj]

I’ll be watching this thread to learn too. I’ve not experienced copper fouling near the barrel’s end, but here’s a few thoughts...

• Barrel ID is smaller in that section which increases bullet friction
• Surface finish of the lands and grooves is relatively rough in that section
• Bullet velocity increases as it travels thru the barrel, perhaps near the end it’s fast enough to strip copper from the jacket?

 

[Hoot]

I'm no expert in bore technology but I'd imagine that the heat generated by the friction of the bullet racing down the bore makes it get hotter as it progresses. I am very familiar with copper as a metal however and it certainly gets softer as it gets hotter. Softer copper rubs off easier. Add to that, if the barrel is lapped using conventional methods, the lapping slurry tends to get less aggressive the further down the barrel it progresses from the breech, removing less steel. That's actually a desirable property in 22 caliber BR barrels. They choke down slightly as you near the muzzle, which improves accuracy. I too have seen the buildup get worse, the closer to the muzzle in my 6mm XC barrel, having gotten it after I got a borescope. It now has about 300 rounds through it and the rate of buildup from shooting nude bullets has not gotten much better, despite it having been lapped at the manufacturer. Its pretty smooth compared to some barrels I've gotten, that claim to have been lapped. So the heat factor may be a greater contributor. Lately, I've taken to shooting bullets in it that have been tumble plated with HBN. Using MoS2 or WS2 has the same effect. Switching to plated bullets stopped the copper buildup instantly. I have not seen the use of a bronze bore brush when cleaning, have a significant impact upon removing thicker copper buildup. It definitely knocks out the carbon buildup however, with just a few a passes, using a good solvent. While a few patches of KG-12 copper remover, after patching out any other chemical you were using to clean the bore, with a strong degreaser like trichlorethylene, knocks out the lesser copper buildup, it doesn't get the thick streaks out near the muzzle. That takes some elbow grease using JB compound diluted with Kroil. That definitely get the bore down to just the steel. That's what I did prior to switching to HBN plated bullets. No more copper. From my own experience, it takes more than 20 rounds to break in most barrels, unless you're using Tubb Final Finish or Neco Bore Treatment abrasive type bullets. While I don't use those, I've read that they get the job done faster. As always, YMMV.

Hoot

 

[AllenOne1]

You could just cut that last 2" off the barrel and be done with it.

But I would probably mix things up using Bore Tech copper remover and/or Eliminator and get all the copper out.

 

[spudgun]

You could just cut that last 2" off the barrel and be done with it.

But I would probably mix things up using Bore Tech copper remover and/or Eliminator and get all the copper out.

Why didn't I think of cutting off the 2"?? Great Ideal will get right on it. LOL.

I am using different solvents to try to get rid of it.

My old factory savage barrel shot the best groups at 600 yds when it was dirty. Shot too many rounds and wore it out over the 3 years.

Thanks for the advise.

 

[spudgun]

I'm no expert in bore technology but I'd imagine that the heat generated by the friction of the bullet racing down the bore makes it get hotter as it progresses. I am very familiar with copper as a metal however and it certainly gets softer as it gets hotter. Softer copper rubs off easier. Add to that, if the barrel is lapped using conventional methods, the lapping slurry tends to get less aggressive the further down the barrel it progresses from the breech, removing less steel. That's actually a desirable property in 22 caliber BR barrels. They choke down slightly as you near the muzzle, which improves accuracy. I too have seen the buildup get worse, the closer to the muzzle in my 6mm XC barrel, having gotten it after I got a borescope. It now has about 300 rounds through it and the rate of buildup from shooting nude bullets has not gotten much better, despite it having been lapped at the manufacturer. Its pretty smooth compared to some barrels I've gotten, that claim to have been lapped. So the heat factor may be a greater contributor. Lately, I've taken to shooting bullets in it that have been tumble plated with HBN. Using MoS2 or WS2 has the same effect. Switching to plated bullets stopped the copper buildup instantly. I have not seen the use of a bronze bore brush when cleaning, have a significant impact upon removing thicker copper buildup. It definitely knocks out the carbon buildup however, with just a few a passes, using a good solvent. While a few patches of KG-12 copper remover, after patching out any other chemical you were using to clean the bore, with a strong degreaser like trichlorethylene, knocks out the lesser copper buildup, it doesn't get the thick streaks out near the muzzle. That takes some elbow grease using JB compound diluted with Kroil. That definitely get the bore down to just the steel. That's what I did prior to switching to HBN plated bullets. No more copper. From my own experience, it takes more than 20 rounds to break in most barrels, unless you're using Tubb Final Finish or Neco Bore Treatment abrasive type bullets. While I don't use those, I've read that they get the job done faster. As always, YMMV.

Hoot

What plated bullets you using?

I shoot 600 and 1000 yds with my Hornandy and Berger 140 gr.

 

[cmillard]

Here’s a trick.....get a soaked patch with ammonia solvent sent down the bore. Then take another patch and saturate with hydrogen peroxide. EVER so slowly push that down the bore. As the patch gets close to the muzzle, fizz will come out. Your patch will have thin strips of copper in it. The reaction of the 2 chemicals lifts the copper right off the bore

 

[spudgun]

Here’s a trick.....get a soaked patch with ammonia solvent sent down the bore. Then take another patch and saturate with hydrogen peroxide. EVER so slowly push that down the bore. As the patch gets close to the muzzle, fizz will come out. Your patch will have thin strips of copper in it. The reaction of the 2 chemicals lifts the copper right off the bore

Really, I will give it a try on my old barrel to see if it works.

Thanks for the tip.

 

[cmillard]

I had a heart barrel 9" twist .300wm that I shot 240 smk out of that copper fowled so bad, this is what I used to get rid of copper

 

[Poor Shot 65]

A borescope, kroil and Iosso bore cleaner. Works 100% of the time.

 

[rwj]

Here’s a trick.....get a soaked patch with ammonia solvent sent down the bore. Then take another patch and saturate with hydrogen peroxide. EVER so slowly push that down the bore. As the patch gets close to the muzzle, fizz will come out. Your patch will have thin strips of copper in it. The reaction of the 2 chemicals lifts the copper right off the bore

I’m certainly not a chemist... but the combination of these two fluids sounds like the making of an etching compound... using it first on an old barrel is a really good idea!

 

[Hoot]

A borescope, kroil and Iosso bore cleaner. Works 100% of the time.

+1
Iosso, Flitz, Rem 40X Bore Cleaner and JB Bore Paste dilluted in Kroil, all do a good job.

Hoot

 

[mikecr]

I’m certainly not a chemist... but the combination of these two fluids sounds like the making of an etching compound... using it first on an old barrel is a really good idea!

Maybe if you added vinegar.
But I've been using Sweets/peroxide for decades, no problem. It is not the last step in bore cleaning, and will be completely removed.
Picked it up per Speedy Gonzales cleaning method: https://www.brownells.com/aspx/learn/learndetail.aspx?lid=13001

Also, don't ever use 'Flitz' on bores. It's more polishing than lapping, and it will increase copper fouling.

 

[cmillard]

I’m certainly not a chemist... but the combination of these two fluids sounds like the making of an etching compound... using it first on an old barrel is a really good idea!

No, it’s an old bench rest technique for copper fouling

 

[David Milisock]

Couple questions.

New Barrel, 6.5 Creedmoor.

Broke the barrel in with 30 rounds. Shoot clean, shoot clean etc...

Getting great groups with my reloads.

Notice heavy copper fouling at the last 2" of the barrel.

I have cleaned with hoppe's copper remover and can get about 90% of the copper but keeps coming back.

The question I have is what is your thoughts on using a brass brush on the bore to remove the copper?

What could cause this to quickly Copper up at the end of the bore?

Load Data: 140 Gr Hornandy HPBT Match, 2670 - 2700 FPS.

Who made the barrel? I'm assuming it was lapped?

 

[46and2]

Who made the barrel? I'm assuming it was lapped?

I asked the same question in post #3. If it's a burr it might take some Tubbs Final Finish to smooth out.

 

[spudgun]

Who made the barrel? I'm assuming it was lapped?

Wilson barrel

 

[Hoot]

What plated bullets you using?

I shoot 600 and 1000 yds with my Hornandy and Berger 140 gr.

Sorry for not answering your question in my last post. In my 6XC, I have used 105 Berger Hybrids. 108 ELD-M (most success) and the 110 SMK that I plated with HBN. In my 260, I've used 140 SST and 142 SMK plated. Went out for the third time this week, this morning doing some jump testing with both rifles and still only needed a few Kroil patches to get the carbon out. No copper. I also plate bullets for my .223 Model 12 and 6.5 Grendel AR with similar results.

Hoot