[Alan Anderson]

I'm going to make a wild guess that you're using buttons to run the shooter motor. One button runs the motor forward when pressed, and stops it when released. The other button runs the motor in reverse when pressed, and stops it when released. Is this what you're doing?

If so, you need to change it. Have one button run the motor forward. Have the other button run it in reverse. Stop the motor only when neither button is pressed.