I have been doing my one shot and clean on my new 6ppc. I am at 8 rounds one shot and clean. No signs of copper thus far. i am using a little KROIL in my hoppes to get the powder out and just a little copper solvent with a patch and jag. Like i said no signs of copper. Should i use a bronze brush to see if there is any copper hiding anywhere? How many one shots and clean do i need to do? Is a bronze brush a no no?? Thanks Lee