Boys AT rifle disabling vehicles

Dear DICE, I have been playing with the Boys AT rifle for a while, I find the rifle good in use and it fits its role. My question for this rifle is: How do you disable vehicle tracks, turret and engine especially the tank. I know how to disable the tank two rear shot in the engine will disable a tanks engine. To shot from back or front in left or right track of tank will disable the track I think. I can't figure out how to disable the turret of a tank, I have tried so many angle and there is simple formula for this. Please DICE tell me the formula for disabling the turret with the Boys AT rifle and where or how to shoot is. Also the formula for the tracks would be appriciated!