I experimented alot with moly coating cast bullets, and the results were not satisfactory, it did not eliminate leading and accuracy also suffered. It would not make the bullet any harder. On the slow side, with soft lead and bullets .001 or .002" over bore, it was okay, but when I hardened the bullets up and drove them faster started having problems, so I quit. It almost seemed as some acted "slicker" then others, and "gripped" the rifling differently, causing flyers, leading(small amount). At the higher speeds, regular lube(with carnauba) just seem to do much better.
Some folks requested it of me and I did them up for them and heard no complaints however, and would do them again because it was/is very easy to do, and in theory, it should work, and can leave the bullet unsized as some folks like.