i found out that the best primer gun i've used is my industrial 2.8 gal pressure pot from work, its got a devilbiss HVLP gun with a 2.0+ tip (cant remember for sure). there is so much adjustment with pressure you can get the primer to lay down extra smooth, plus with the pot you can mix an entire gallon at once, and without a cup on the gun you can shoot at any angle you want. its marvelous!