I shoot a .308 with 175 gr SMK at 2700 fps or so.
The "come up" from 100 to 1000 yards is about 35 moa. If velocity is lower, it could be as much as 40 moa. The JBL site will tell you.
So set it a yard high at 100 and you should be close at 1000, if your target is well enough defined.
Back when the 1903 was shot seriously, they made little micrometer adjusters for the ladder sight so you could make finer adjustments than the hardball range markings allowed. But they are themselves collectors items now.