RE: Black breech plug?
That sounds like just fowling from the 209 primers. That is normal. When I shoot my Black Diamond XR the breech plug is black, the bottom of the scope is black, the striker is black, it's a mess. But, that is normal. Just be sure to use a good solvent and scrub that off. I like to make all parts of the rifle shine like the day it came out of the box.