Barrel fouling versus pitting

[TARNATION !!!]

Not to be confused with "fowling and pitting" which would be posted as a migratory bird hunting thread.

I'm still playing, when time permits, with "second chance gun". I did have the barrels re-blued after eliminating a lot of external rust. I did not have them honed and have been working them with Hoppes and a brass brush on a rod attached to a hand drill. Whenever I find myself in the basement and get distracted from whatever the reason was that I found myself there, I run the brush through a few times and then a patch and a light swab of oil. So far, the patches continue to come out black. Some of the bore glistens but there are many areas that do not. I have taken a small wooden dowel, trimmed the end to a thin flat chisel like edge and run it over some of the non-shiny surfaces. I cannot detect any noticeable "feel" of a drop into pitting nor a rise over some lead fouling. The dowel seems to glide effortlessly along the bore surfaces, be it a shiny area or the not so shiny areas. I then tried steel wool wrapped over a brush for a bit more aggressive approach. No noticeable difference.

I have never dealt with bores like these, as my own guns have never been allowed to deteriorate. I'm thinking they have to be as clean as they can get after all the Hoppes and brushing with the drill. This makes me think it is a lot of areas with slight surface pitting. Not unreasonable, given what a rust bucket this gun was when I took it on. But.......... why do I still get blackened cloth patches?? Thoughts??

Cheers,
Jack