[Unclenick]

You may want to protect it anyway. I find the Evaporust will discolor and eventually slightly etch a plain metal surface. Of course, I saw this experimenting with nails and left them in it overnight. You don't need that much exposure. Nonetheless, I wouldn't get it where you don't need it.

When you finish with the rust, you might consider firelapping the revolver, at least lightly? That will tends to dull sharp edges on pits that would otherwise scrape lead off bullets and accumulate it.