Ok ok let me clarify. The key is the key from the trigger lock that I bought from CT. The key is yellow so I just assumed it is brass.To be honest with you I have no idea if it is brass or something else, but it is yellow.
It looks like a smudge/smear but it didn't come off when i rub it off with a piece of cloth.
Have you tried bore cleaner yet? Anything that removes copper fouling will remove a brass smear.






















































