Plastikote is my first choice in primers . . . all their colors, but I prefer grey. I use that exclusively these days. I usually let the paint gas out over night, but if it is humid it will take a little longer. I'd say give it a little more time and then see, but it should not be sticky after 48 hours. I'm also assuming you prepped the body correctly by washing it with warm soapy water and a toothbrush?