03A3 Sight - Calibrated for M1 or M2 Ball?

[MilSurpFan]

M2 ball was standard when the 03A3 was developed . M1 ball was developed around '25 and some was issued in ,27 , but due to vast supplies of M1906 ball , not widespread till '36 or so.
By '37 , M2 ball was being re-issued , named M2 in '38 , and was adopted as standard on Nov. 9th , 1939.
Chris

So are we saying the A3 sight is calibrated for essentially 150 gr. flat base moving at say 2740 fps. ?

Any chance the M1 is a more accurate or effective spec? (Idea here being to pick a spec to handload to that will work with the sights, but be effective for hunting if I ever use the rifle for that.)