When I have shot with my 17-3 there are built up some burned powder 6 places on the edge of the front of the cylinder. It is about 1 x 2 mm in size. Do you all get this kind of burned power build up? ...it is hard to remove so I will ask for a good advice on how to remove it.
I can't recommend using the green 3M brite pads. It will remove the power but also the blueing. The blueing surface was not as hard as I thought. I did a re-blue by hand and now it looks ok again.