Have no idea after flying the plane for so long.. I have been puzled since the start.. I just know it works when you are "on" and it is effective at close ranges. Some fellas boast about their shots up and past .50M and I can't hit a barn at that range.
I suppose this is is redundant; but if it is under the nose, shoot. Otherwise the slow projectile will not hit anything if you have target fixation..
That scribe in the manual says it all: "Don't fire until the other aircraft fills your windscreen".
I do so-so with it and still am annoyed when the results are not up to my expectations. although, it can be highly rewarding and frustrating at the same time. I get the same feeling when I am flying a P-51 and make the long shots knowing it will be ineffective unless my aircraft has a huge speed advantage over my opponent.
Still a No0b and nothing more, everyday is a new learning experience in this Game.