Agreed sketch, and heres the thing.  Most people in the game eiter don't know, or don't believe that the osti is effective out to those ranges.  I have actually had guys tell me to stop shooting at planes that are 1.5 out because im wasting ammo.  This is actually a good thing though, because most guys in AC will pay you no mind if they don't have icon on YOU.  A plane that is lazily circling your field at 2k out is great practice for long range gunnery.  Also, shoot at buff formations from way out, there is a lot there to hit so people can get a feel for the range.  Another tip,  If an nme passes over you and egress straight out and up without jinking because they think you are out of range aim a good bit high on that same heading and just hold the trigger down and wait for them to fly into the stream.  It's not a high odds shot by far due to the 37mm's rate of fire, but if you don't shoot at em, your not gonna hit em.