yeah you don't have it thinned down enough, in the Paint business that is called Orange Peel.
So as you are stating you are spraying it at 10 parts paint to 1 part Reducer = 10% reduction
Blitz Black and Medium Gloss Black (JD) is synthetic enamel and needs to be reduced to 25%
4 parts paint to 1 part reducer.
Sprayed at around 45 psi at the gun
Recommended 70 degrees outside air temperature.
with a 10" wide spray pattern
with a production grade Binks model 7 Spray gun, siphon feed.
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Just for comparison Ditzler and Dupont's single stage Acrylic Enamel gets reduced 33%
3 parts paint to 1 part reducer.
Just so you know you are in the ball park.
At 10 to 1 that is spraying out way too thick.