There are many types of auto paint. some acrylic, some lacquer, some polyurethane. All are put on over some sort of primer, after some surface preparation. Take it to a auto shop and see what they would charge to prep, prime, and paint the drum. They will do a better job than the average joe. Some acrylics and polys are thinned with a product called "dryer" than chemically allows the paint to dry quicker and harder. Talk to them about the process. They may blow you off, but in slow times they may help.