another thing to try, and i'm not sure I know how to explain this...
if you really wanna damage 'em, you have to concentrate your fire at one single spot on the nme plane.
So for example when you were diving in on the zeke, you were probably pulling up on your j/s, so the bullets were spread out all over the airframe, and doing little damage. If you time it when you inin the nme, and keep your joystick lvl for a second or two when firing, all the bullets hit one spot and do some pretty major damage. To pull this off, you should aim slightly infront of the nme, so when you shoot, they fly into the bullets that are concentrated in one spot. Same thing with the snapshot you described.
I'm sure y'all can describe this better than I.... So please, chime in.