Sorry folks; there is no solid, dry substance that won't hold fingerprints. If you touched it, there's prints there, whether you can see them or not, and they stay there for a surprisingly long time. Rough surfaces can make them difficult to read, but they're there, none the less.
If you doubt this, try this experiment: Take an item that you think won't hold prints and touch it lightly. Now put it in a sealed container (glass jar, etc.), along with a cotton swab containing a liberal amount of superglue. Don't let the glue or cotton touch the object; it's not necessary. Let it sit overnight, and the next day, your prints will show up in vivid white. (There are ways to speed this up, but it involves HAZMAT)
I wouldn't try this with a gun though. The prints are literally superglued to the surface and are a real bear to remove.