OzMike,
If the checkering is worn flat, at least you know it has been carried/hunted with a LOT. But, what you don't know is:Was it used mostly as a "slug type gun" or a shotgun. IF it was used a LOT as a shotgun...what is the condition of the rifling...? I'd check it out VERY thoroughly as to leading in the forward end. Just a thought, SP2
PS. Ya never know when a good cleaning will turn a sour bore into a good shooter.