Jeff, have you tried several brands of ammo?
i.e. I have heard wolf steel sticks in some guns, while blazer aluminum does funny things sometimes
If you really want to just clean it up, use soemthing like rouge (sp) polishing compound and use it lightly and not too hard, you don't want to use a power tool and leave a big indentation
I know that gunsmiths do this, but I would be leery of doing anything that is more than a little bit.
Ask Policelugers (AKA Howard) he's a gunsmith and would know far better than me. I also suspect this is a stainless luger? It is unknown to me if the lugers ever had galling problems? I think not, but early stainless guns did...
Ed