[RickB]

Are you trying to add finish, or remove it?

I bought a repro ramrod for a muzzle loading musket, and to match the overall patina of the musket, I stood the ramrod in the corner of my shower for a week, then worked it over with fine steel wool, removing the rust but leaving some staining; looks great.

If you are trying to remove finish - bluing - I'd be very careful with chemicals, like muriatic acid, or naval jelly, as it's going to be all-or-nothing; very difficult to control.

Some kind of accelerated abrasion would be my first choice. Maybe rubbing it on a piece of well-used carpet, like a door mat?