Hmm, you don't wait til they're outside your turn?
no, I just wait till their nose is pointed in front of my plane, like they are about to shoot. Then I break hard into them, and pull up and do the barrel roll with some rudder. If I need too, I'll drop flaps at the top and cut throttle too. This way I blow a ton of e and they shoot right through the barrel roll. Then they often pull up, giving a great tater shot. there is a great film on you tube full of this move (barrel-roll defensive).
more experienced sticks will spot it and try and lag behind your turn or roll the opposite way when they see you begin the reversal, then they stay flat or turn out away from you. Most wont though and boom, boom they go.
