Get ya some JB Nonembedding Bore Paste (other such might work as well but JB is all I've used) and liberally coat all the contact surfaces with it. Now open and close the action 50-100 times.
Clean ALL the JB off and lube it up properly. If that didn't get the job done do it again. The worst of them I've had to smooth up were done by the second time. Now if you have any really major burrs or gouges ya might want to first clean that up with some very fine 800 grit or finer sandpaper or crocus cloth. Be really careful with any sandpaper and use it on as small an area as possible and ONLY if there are really bad looking areas.
Normally the JB will smooth up any double gun or hinged single for that matter..