tips for spraying primer

Hey OldVart I am using the 4:1 primer....thanks for looking for me...so if i use this reducer, it should help me out when spraying over the solvent pop? how many coats do you think i would need, and how much would a gallon of high build cover for me? Also dgc333, i applied about 3 coats of high build with a roller a month ago...sanded that down and got solvent pop, so i sanded the primer down to the point where most spots the paint underneath or bare metal was showing through....i then rolled on another 4 coats of high build, giving about one hour of drying time between each in order to fill in the solvent pop and prevent it from happenning again....that was about 2 weeks ago...i have now sanded that application down to where the original paint is showing and i am still getting solvent pop....would this still be a candidate for a problem? OldVart, do you know anything about this at all? I just want to make sure that this next step of me spraying primer isnt going to be a waste again...i want to be sure that i can fix the solvent pop and move on to the final sand, and then paint

thanks so much guys so far
Matthew