No need to get excited about POI differences with different ammo. And there is definitely no way of knowing what load will hit high or low--until you shoot it. Faster loads can shoot higher or lower, and the reason has more to do with the shooter, than the ammo. Heck I have watched different people shot the same ammo to different POI's.

Barrel length, barrel weight, and recoli have a lot to do with POI. As well as individual shooting habits. In a lot of firearms a faster bullet will hit lower because it spends less time in the barrel, so the rifle is unable to recoil as high as the slower load.

Consider it a blessing when you find a firearm that shoots to the same POI with different loads. And when you find that you will normally find that rifle quality, and barrel stability have a lot to do with it, along with shooting form. Tom.