well, progress has been made. Chamber polished, and I scrubbed the bore a first good pass. I opened a brand new phosphor brush, and it ate it...no more than 10 strokes and it didn't fit tight anymore . Scrub a dub dub, clean out solvent, switch to jb paste and kroil, flush all out, and here are the results. With the rust out, there was some copper under all the crud.

from the muzzle...my camera rod is only 24 inches, so not quite to the end
birds eye view...

side view...


I've seen worse shoot great, and virtually brand new shoot not great...but I think I'll get a new barrel. I'll let the threads on this one soak while I look for a good condition original (I don't have my hopes up), give the receiver another good going over and test fit parts from my original Kragicon to make sure fit and function are acceptable, then buy a criterion barrel.