The nozzle will elongate over time in the direction of the fan. It is believed that the fillers in primer will erode the nozzle faster. Hold an old nozzle up to the light and this elongantion will show.
I shot gelcoat on this replacement right wing yesterday........heated the paint to about 80f, which helped, but it still needed 10% thinner. Two wet coats gave orange peal to the max. Shot a 'leveling' coat with an additional ounce of thinner and fan opened up with gun a foot above the work........it looks pretty good. Must have 30 pin holes in places I inspected with a light and even a magnifying glass..............where (how) do they form? Catalyzed a tad of paint and filled the pin-holes with a tiny brush. The bump will disappear with wet sanding.......hopefully with 800 wet and then buff out after curing for about a week.
I hate painting, but it is the final thing that must be done after a repair!
;) JJ