Years ago, I was a pawnbroker, and as a jeweler, we were always polishing something.
I had put my polishing tools away long ago, but today, I got something out of storage.
This was a barrel that showed typical bluing marks as the slide worked back and forth around it over the years. It had the tell-tale Glock smile as seen in the one still in the gun.
A hour later, and a few changes of polishing compounds, I managed to achieve a pretty nice mirror finish.
Being a Glock, the blue finish, what Glock calls "anti-reflective finish", covered up a rust prevention metal treatment called TENIFER. Tenifer keeps metal from rusting, and also makes the surface of the metal harder.
The anti-reflective finish is gone, but what is left, polished Tenifer (goes deep into the metal, cannot be polished out) looks like it belongs in a car parade somewhere, attached to a chrome bumper.
To further protect the finish, I washed and polished the barrel in Teflon. You cannot see it, but it is a dry lube, that will keep anything from sticking to the metal, or even touching the metal. Water, salt, dirt, gun powder, led, should all just flake off.
I will do the Glock slide next. Will post pics of the finished pair.