If it shoots well even when coppered, then no big deal. Both my pre 64s copper up fairly significantly. More so than any other of my rifles. May be the exception, but they still shoot well and therefore I don't get all that excited about it.
With a couple Douglas and a Bartlein barrels you can hardly see the copper until you patch. With the pre-64's after 20-or less-you can often see the bronze streaks.
I clean them when the season is over. Wipeout makes quick work of the copper. Takes a little more time than the other rifles, but I don't have to sit there and watch while it does its thing.
Again, if it shoots well it is doing well, and you are good to go. If it doesn't then there are others issues to be worry about.
Addition: All mine shoot more consistently after some copper has been laid down and I'm not all that anxious to remove it. If you have a shooter and it wants to keep shooting with copper, then let it tell you what it wants. After all it is a big part of the team.
