bronko22000

I think I would like to agree with cayugad on this... it really could be left over machining residue caught up in the pores. The CB cleaning fluid and the MX-BC will leach stuff out of the bore and from behind the lands. Personally I think it takes a couple of applications to get all of the old stuff out of the barrel bore....

I did not know your Silver was a PRB gun until I read your other post.... But when you first talked 'grey' my very first thought was lead - now that I see you are shooting PRB's - I think it might be lead.... but you have to remember I am a junior novice rank ameture at shooting a PRB's.... but if your patches tear on the way down or on the way up and the ball is exposed to the lands and grooves - lead fouling begins... just a thought....