Gargoyle
Finder Outer

I've tried to remove copper from barrels using the same product, but there comes a point the copper takes on a resistance to the copper solvent. Like, even overnight soaking and the copper remains. I had an idea to use a product and then follow it up with alcohol patches and then 10-15 passes with a bronze brush soaked in alcohol. I think this accomplishes removing the copper solvent and then etching the remaining copper, making it more porous to dissolve away.
I took two heavily coppered barrels, both 416R stainless, and tried a single product multiple times. It was when I rotated through the products listed in the picture that there was a significant amount of copper removed per cycle.
Wipeout 30 min sit- alcohol patch through and bonze brush scrub - Hoppes 30 minute sit - alcohol patch through and bronze brush scrub - Hoppes Black Copper 30 min sit - alcohol patch through & bronze brush scrub. All copper gone.
Each time I would see new blue on the patches where before using the same product it would not produce blue after alcohol treatments.