[Eklund89]

Set correct distance and wingspan setting in the sight. Do17 should be 59ft. Range depends on your convergence. If you have convergence 200, set the sight to 420 and 58ft and when the Do17s wings touch the inner lines of the gun-sight you fire. Not at 20 meters. If you shoot at correct distance with correct convergence you can down 10 Do17 with the ammo you wasted.
When you see the rounds go under the bombers when you aim directly at them, correct and don't continue fire under them. Next time, put the pepper just above the target at that close range and you should hit better.