check your convergence, and try to fire only AT convergence. You'll find a hundred theories on where to set them on these boards, but I have the biggest tip there is. Pick a convergence, and stick with it, don't keep moving them around looking for that sweet spot others seem to have. Mine are at 350 for all guns, in all planes. The lead may change due to ballistics of different guns, but I know if I hit at 350, Im going to do some damage. In your film you were hitting, but just not a concintrated amount.
Set your convergence, leave it there, and practice !