Hi All, new to the site from Maine. I thought I had a copper fouling issue with a couple of rifles. Yesterday after returning from the range and cleaning and cleaning and clea....I thought hold on here this just can't be. Everytime I put the bore brush thru the barrel then patched it, it came out blue. I then used solvent and dry patches untill all was nice & white. Run the brush thru again(4-5 passes) followed by a patch which came out blue again. I had only shot 10 rounds and the barrel was thoroughly cleaned prior to the range trip. This rifle was used but appeared as not much. I've seen the same thing on brand new rifles. I dipped my brush into the solvent( Butches Bore Shine) several times and brushed it out then again and wrapped in in a clean patch... all blue. So it appears like the solvent is acting with the phos./bronze brush creating the blue stain. Anyone have any thoughts on this?