My son, Andy, has been coating firearms, and other objects for several years. I've never tried it, but I've watched him many times, enough to know that I wouldn't try it myself if I wanted a satisfactory result. Take a look at examples of firearms and other things he has done. He has a lot of equipment most of us don't have, and experience makes all the difference on the finished product. Take a look on his website
Guncoat Northwest. He does work for Police, Prisons, Military and Civilians. Call or email him if you have any questions; he's a straight shooter.
beemerrider