You can also use that LCG (lead computed gunsight) in TA or offline, to shoot drones. Ctrl TAB until friendly lock is enabled (if you want to shoot greens, disabled for reds obviously) then hit TAB until you go tthe maker around the plane you need it to. Offline you might have to check arena settings (in FlightModeFlag make sure the LCG is checked), save arena settings after changing them).
Tracers on or off - mine are off, simply because they distract me and i dont need them for aiming. You can use them to know, if you miss, why you missed.
Aim: The main thing IMHO for gunnery is: get up close and personal (d200-400) and shoot only short bursts. Dont 'walk' your bullets onto the target while firing.
Apart from that: You need to take into account bullet ballistics, muzzle speed, your speed, target speed, angle off and tons of other things. Since i dont have the capability of a gunner computer, i just learned from experience, how the gunsight picture looks when my bullets hit.
My recommendation would be: Stick to planes with the same gun model for starters. Be aware though, that the different 20mm canons have a very different ballistic (hispanos being the best and easiest among them). If planes have more than one gun type, fire them seperatly.
Im sure youll learn fast. Good luck

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