If I am interpreting your description of the finished product , I am guessing that you have metallic sag and / or " marbleling ". Is this single stage or base coat/ clear coat. If it is single stage, this is common. Metal flake sag or accumulation happens with high flake content . Some paint suppliers add too much flake to the mix when they mix up your paint for you. You need to be aware of the high content and constantly mix your source / supply before dunmping into the gun cannister. While you are spraying, repeatedly take time to mix the contents in the gun. As for marbleing, that can be taken care of on the final coat. The final coat should be a light misting coat holding the gun almost 2 feet from the surface. First coat light, second coat wet in the opposite direction. 3rd coat ( if necessary ) opposite direction from second. Final coat, cut down on volume and hold gun 1 1/2 to 2 feet from surface and mist the surface. This final coat will smoothe everything out. I have never encountered any marbleing in base coat clear coat, but you can do the same thing on your final base coat if you encounter marbelling. If the metallic sag is extreme add reducer quickly to the mix and spray lightly to soften the paint and hopefully move it around to an even pattern. The marbleing and metallic sag is quite common.