What Ray sed (kinda).
Thin it with Tamiya lacquer thinner for best results. When airbrushing lacquers, often best results will be had using a considerable amount of reducer/thinner. This could very well solve your texture issue- just add a bit more thinner. It will help the issue of the primer partially drying in the spray stream and 'bumping up' as you apply it.
And if the thinner you're using is incompatable with Tamiya sprays, orange peel is just one of the horrors you could face.