[barn34]

First of all, to successfully implement PID control, you have to tune it properly. We found that we needed multiple PID settings based on set point to give the most desirable control response. You can find information on PID tuning by googling it. There's plenty of info out there to help you get started.

Secondly, you always have to account for a certain amount of settling time. This means that you have to allow your motors time to get up to the desired speed and then reach a steady state at that speed for a consistent shot result. Nothing is instantaneous, no matter how good your PID tuning is. You can account for the appropriate required delay using various programming techniques.

Lastly, the delay required to account for settling time will vary based on several factors. Current battery charge and the desired set point being two critical ones. If you are clever, you can also account for these factors by tracking them and implementing corrections/adjustments in your code.

Make sure to focus on properly accounting for the factors that you can control (battery charge, desired speed, etc.) and minimizing the effect of the ones that you can't control (variations in ball mass, ball surface consistency, drag, etc.).

Hope that helps set you in the right direction.