[acrashb]

Not to worry.  There is no internal finish to wear off - it's streaks of copper from the bulles.

Hoppes 9 doesn't remove copper (pretty sure), so some is left behind.  You can ignore it or, if it bothers you, switch to a cleaner that does strip copper.  I like Shooter's Choice "MC #7 Bore Cleaner and Conditioner".  So do benchrest shooters (combining it with Kroil).

After you brush, run rubbing alcohol across the brush to remove the cleaner - otherwise the brush will dissolve - it's copper too.  I just hold the brush over a garbage can and trickle alcohol (99%) on to one end, letting it run off the tip carrying debris away.

 

[acrashb]

Quote[/b] (alex @ Mar. 04 2005,6:18)]

Quote[/b] (acrashb @ Mar. 03 2005,9:56)]the brush will dissolve - it's copper too.  

brushes appear to be copper but actually "phosphor bronze".  they might disolve, i dont know

You're right about the brush material - I was simplifying - bronze is just copper, with zinc, tin, and lead added to improve its characteristics (like rate of oxidation).  I think the phospher is added to make the material more elastic (not sure).  And yes they do dissolve - the symptom is the brush gets much easier to push through, and the diameter of the bristles goes down quickly.