Not sure I like this picture. Should I be concerned about the dark shading in the throat? Haven't bought it yet so I haven't tried to clean it up.

Can u clean it up first an post another pic. Doesn't look promising like it is

Hard to say from that photo...Run a patch thru it and look for crisp rifling that's square at the beginning of the rifling, and a shot out throat with be shallow for a half inch or more, looks wallowed out...color means nothing as a rule unless its rust..that should wash out. The lands in the picture look square and good, but I would dare judge a dirty bore in a photo....

All I can really make out from the photo are parts where brass and bullets have touched the surface and what appears to be a lot of powder fouling. Difficult to tell. Definitely needs a cleaning, which in itself is not a good sign. I would never try to sell a rifle that dirty.