To add to Lusche's great suggestions,when in the TA turn on the LCG.
This is done by using crtl+tab to enable friendly lock,then use tab when your target is in sight.
You will see the lead calculating gunsite project a set of crosshairs,put then in the piper and watch the hits land. This will assist you in getting an idea of just how much lead you really need.
Hope that helps.