Bore cleaning?

[Kansas Jake]

It would. It doesn’t evaporate real fast and tends to absorb into rust. There are probably other products just as good but it works well for me.

 

[Blackpowder Therapist]

Some idiot let my smokepole's bore get rusty. How does an idiot...errr...how do I best clean it and smooth it out?

The advice about scrubbing is some good advice.
I'd also pick up some frog Lube extreme lube. Soak it on a patch and run it down the barrel let it sit overnight. It will draw out the old fouling.
I use it exclusively in my competition rifles