I've read every thread on zeroing the Aug 1.5 optic for 300 meters, what ammo is the AUG factory scope calibrated for ?

That's a good question and not an answer I know.

On Steyr Mannlicher bolt guns, the current .308 load used is federal gold match 168gr.

The old Austrian AUG's don't list the ammo used on the test targets, but from the barrel twist and that time period, I'd guess that they used a 55gr factory load.

Zeroing at 200 meters should probably be done with your preferred ammo. Some guns prefer particular ammo over others, I say find something that is supposed to be good and go from there.

Not much help, sorry.

It is highly likely that it is calibrated for NATO standard SS109 meeting STANAG 4172.  The SS92 (M193) 55gr. was discontinued for military use in the '80's, outside of training (possibly).  

For Austria's military use, there's basically only one choice, SS109, and it is likely that the proofing and test fire is done on the same line for both civilian and military AUGs, so military ammo would be used.  If you use some M855 (SS109 equivalent), you should be on the right track.