I can't speak for Kirby, but that won't stop me from guessing [img]/ubbthreads/images/graemlins/smile.gif[/img]
Kirby is at a disadvantage here, as the barrels he uses don't have a copper fouling problems. The first gun Kirby built for me ( 300 RUM, Lilja 30" # 8) - had virtually no copper fouling when I did the break in. The next two RUMs he built for me also had little to no copper fouling.
I doubt Kirby would argue with Lilja
Q. What does Lilja Rifle Barrels think of the use of bore solvents with ammonia?
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A. While we're aware of "bad press" associated with the use of cleaners with ammonia as part of the solution, we have never seen any damage in one of our barrels caused by the use of ammonia. The rumor is that copper-removing cleaners with ammonia will pit and damage the interior surface of a barrel. Ammonia is very effective as a copper remover. We use solvents, such as Butch's Bore Shine, to remove copper during the break-in. We routinely leave Butch's solution in the barrel over night too. Again, I repeat, we have never seen a problem with ammonia in the concentrations found in commercial cleaners, in either our chrome-moly or stainless steel barrels. This includes examination with our borescope.
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