It sounds like you are rushing the process, especially with Halloween being aroudn the corner. My advice is like others, but I stress taking your time and letting coats to FULLY DRY before puttign another coat on. I would recommend Pep Boys autobody primer.. I have had nothing but love from that primer. Then WASH your pieces...dry them. Dust coat your primer...don't mind that some areas are not fully coated wait for about five minutes, do it again, catching all the unpainted patches...do it one last time to get it all. Wait until all coats are dry. Go get dinner or something. Then add your first coat (very light). Get a snack or a beer. Watch a show. Then second coat...watch that second episode of 24 or something. Then finally a third.
The problem with rushing a job is that the bottom coats never dry. If those don't adhere, you could take your nail and scratch it right off easy.
hope it helps.