I've been hunting for my second bear and it's been raining pretty much since the season opened on Oct 25. I wipe my rifle down after every day of wet hunting and give it a minute shot of royal purple down the bore after the rifle drys to room temperature. I noticed last time I cleaned it after a little range time there was what I thought was rust in the muzzle. I took a closer look and realized it was copper. I swabbed and swabbed with what I thought was good copper solvent (Pro Shot) that's worked great on all my other firearms. Finally gave up. I switched up ammo for bear season so I of course went to the range again and after less than twenty rounds I swabbed and swabbed and swabbed. With patches and brushes still cant get the copper off the lans of the rifling. I think not more than a couple inches down the bore from the muzzle but Im not sure. Any suggestions or advice. It hasn't seemed to affect accuracy yet. Still holding 1" to 1 1/4" groups at 100 yards with 250gr Swift A-Frames. I'm just afraid it's still not good for the copper to be in the bore. I dont let the barrel get hot. Always let it cool between three shot groups. I Can usually dial it in, in no more than three groups and swabbed the bore after every shooting session. Weather range time or hunting. I Just cant seem to get the copper fouling out.