Pat, that jibes with one of my cures which is to use Break Free and very fine steel wool. Unless the rust is deep, it seems to be ok with the bluing.
Another good one is to get a pack of the "Wipeaway" cloth that the pistol guys use to remove lead fouling in their forcing cones. It's like a yellow felt, chemically treated. It turns brown as you rub the rust, and will even remove unseen rust. The downside is that it will remove bluing too if you overdo it.
HM