I have been in the process of breacking in my 300 wby barrel. I am going through my normal break in routine. First 10 rounds, I clean after every shot. I then start cleaning after every set of three. While doing so, things seem to be going O.K.. I swab, brush, and then swab until I got clean swabs. It appeared to be doing as usual. When I get home I notice I have major copper fouling. My question is, what is the best way to clean copper fouling. Ive tried my normal methods, leave nitro solve in the barrel for a couple of hours and then clean until all blue or green is gone from the swabs. I get no blue or green from my swabs. Am I getting old and my eyes playing tricks on me? I can see the copper in the rifling, but it will not come out. All advice is appreciated.