51Chev, don't follow the old bigger is better for primer theory. Depending on the primer being shot, it may be better. Without a long story, I did a test one time that gave me MORE film thickness with a 1.3 tip than a 1.7 tip. The droplets are smaller, thus you have less solvents in the film as it is applied. Less solvents=less shrinkage, less shrinkage=more primer build.
What kind of primer are you shooting?
By the way, I have used that gun with base and clear, it works well.
