I would have also used a different primer. Rattle can paint just isnt the same as it was 20 years ago. The VOC laws ruined it. When I was redoing the front end of my wagon I used an epoxy primer and a 2K paint on almost everything. The small pieces that I did with spray bombs are already rusty. I hate doing things twice.
You already used it but for the future I would use a better primer on something thats been blasted.
You already used it but for the future I would use a better primer on something thats been blasted.