JB and Kroil...

[parshal]

I really don't go for perfectly clean. Your gun is going to copper back up in a few shots anyway so once I get most of the carbon out and there's not much blue on my patches I call it good.

I do this too although I don't try to remove the copper unless it's heavily fouled and I've not found that happen with a good barrel. I usually run a patch with automotive carbon remover down the barrel and let it sit for a few minutes. Run another and then some dry patches. The borescope shows no carbon. I don't see the reason to remove all the copper only to deposit more when shooting.

I used JB and Kroil on my factory 264 barrel religiously. I haven't used it on custom barrels.

 

[Mikecr]

I guess neither of you have heard of 'copper fouling out'?
This is when copper builds to a point of constriction anywhere in the bore.
I know there are folks who think copper is their friend, but the truth is there is nothing good about it.

My bores wouldn't 'copper back up' in a few hundred shots, which is not an accident. And they shoot as good as they ever would -with no copper fouling.
But in the past I've had bores that couldn't make it through a 10 shot group before copper fouling out, throwing shots. The only thing a barrel like this is good for is afternoon hunts, followed by proper cleaning to white metal.

 

[parshal]

I've definitely heard of too much copper fouling but I've yet to experience it with Proof and Bartlein barrels (the only aftermarket I've tried).

 

[Mikecr]

The right lapping will greatly reduce copper fouling. That's for sure.
It's just my contention that removing that minimal copper is not a bad thing.

 

[desertcj]

While I will acknowledge that I really don't know, it's hard for me to believe how a bore can be TOO smooth. Doesn't make sense to me, but I'm certainly no barrel guru....

 

[DocDoc]

Perhaps it is like dimples on a golf ball. The aerodynamics are better than a smith surface.

 

[Barrelnut]

While I will acknowledge that I really don't know, it's hard for me to believe how a bore can be TOO smooth. Doesn't make sense to me, but I'm certainly no barrel guru....

Mystifies me too. I thought one of the advantages of chrome lined barrels in ARs was less fouling and easier cleaning.

 

[wbm]

Gunslick foaming cleaner and Wipeout have worked well for me over the past few years in all my rifles. No complaints here with either product.

 

[dmoon]

http://forum.accurateshooter.com/threads/copper-fouling-barrels-why.971336/

 

[parshal]

http://forum.accurateshooter.com/threads/copper-fouling-barrels-why.971336/

The last post there:

if the finish is too smooth,from too much flitz or JB), it will foul more due to increased friction.

seems strange to me. Why does friction increase? More surface area?

 

[dmoon]

That's my understanding, just more surface area. If you dig around on accurate shooter there are lots of posts about copper fouling, and it varies with barrel material. I know back when I used to work in the machine shops I always hated working with stainless as it is more "sticky" than high carbon metals. The guys on accurate shooter explain it better than I can though.

 

[Mikecr]

Slicks provide huge friction(traction) for NASCARs. But there is an extreme energy loss with this, the tires melt into grease, as they burn up.
Just opposite, trains function by virtue of very little contact with rails, which greatly reduces friction.
A well performing corvette needs dead between. This is your barrel.

W/resp to copper. A slick bore causes so much friction that jackets overheat, and copper wipes off into the bore surface (much like a hot NASCAR slick on pavement).
And what causes too little friction(given correct bore dimensions), is roughness that tears away at passing bullet jackets. Again, increasing copper fouling.
Once copper builds to any constriction, shots throw.

 

[desertcj]

Slicks provide huge friction(traction) for NASCARs. But there is an extreme energy loss with this, the tires melt into grease, as they burn up.
Just opposite, trains function by virtue of very little contact with rails, which greatly reduces friction.
A well performing corvette needs dead between. This is your barrel.

W/resp to copper. A slick bore causes so much friction that jackets overheat, and copper wipes off into the bore surface (much like a hot NASCAR slick on pavement).
And what causes too little friction(given correct bore dimensions), is roughness that tears away at passing bullet jackets. Again, increasing copper fouling.
Once copper builds to any constriction, shots throw.

OK, now how would a dry lubricant like moly, hbn or ws2 between a slick/smooth bore and a bullet behave?

 

[LoneTraveler]

Every barrel is a mystery within its self. To me there is 3 types of fouling. 1. Carbon and graphite, This is what's left from the powder burning and the coating on many powders, Some Ball Powders are bad for this. Brake Cleaner seems to work well removing it. 2. Copper wash, This is the very thin coat that attaches itself to the smooth metal area of a barrel and can only be removed by Chemically dissolving it. Sweets or other ammonia type products, 3. Thin slivers of jacket material Copper. From slight rough places mostly at the edge where the lands and groves meet, strip off these thin slivers or shavings of metal. These can wreck the accuracy of a barrel quickly. This is where Kano-Kroil gets its place. Kroil is a creeping penetrator that crawls between the barrel and fowling and releases it for easy removal with a brush or a tight fitting patch.
We the owner and shooter of the barrel have to figure out what the problem is. And then work to remove it. My rifles are like I have about 10 girl friends and have to keep them happy so they keep me happy. Ha Ha.