Hi All,

I'm new to this forum, so a few words about myself:
I'm Patrick, 28 years old, from Germany, and enjoy sports shooting for 3 years now. (In Germany you can only buy most of the fire arms at the minimum age of 25.)

The last rifle I bought in December 2016 was a .22 lr Mark II FVT.
I clean my rifles after every shooting with oil and a bore-snake.
Last week suddenly half of the muzzle changed it's color to orange-brown after shooting.
I tried to clean it away with oil, but did not work.
I tried out around 10 shots CCI MiniMag and CCI Velocitor, both are copper plated.

Do you think that this could be copper? Changed color since too much heat from the HV ammunition?
What do you think, please? Did you share my experience in the past?

Thanks & Regards
Patrick

Pictures: