Airless spray guns will not spit until you add an extension to it. The longer the extension the larger the spits. This is created by the lag time from trigger release at the gun to the end of the extension and the slow drop in pressure. We learn to spray with extensions by never starting and stopping on our surface to be painted. I have a video, on Paint Life TV, on controlling spits when using an extension. You can also use a Clean Shot valve at the end of the gun which will eliminate spits altogether. However the Clean Shot is heavy and causes fatigue and wrist pain when spraying continuously.