Honk, Honk, Boom,
Is your bolt "in the white", blued, jeweled, or chromed? On White and chromed bolts I use a 8" stitched muslin buffing wheel and White Jackson compound. It'll put a glitter on that is better than new. Stay from the lug surfaces and blast it off with brake cleaner until every trace of abrasive is gone. Oil normally to prevent re-occurance.
For the other types steel wool and oil will work. Another option is Kleen-bore gun polish. It'll clean rust up and does a good job on blueing. You can remove rust that you didn't even know you had til you see your cloth turn red. This isn't the kind of stuff you want to use very often, so don't let the rust re-occur.
Dogleg