The question is almost meaningless. If a rifle/ammo combination can shoot 1 MOA at 100 yards, it can mechanically do the same at any distance out to its maximum ballistic potential, provided the shooter can compensate for wind effects. The maximum ballistic potential is determined by the bullet's BC and the muzzle velocity (along with environmental factors).
So there are two parts-- how accurate is the rifle with the ammo in question; and what are the ballistics of the bullet/mv combination.
The maximum potential accurate distance is usually where the velocity drops down to 1200-1300 fps, some more, some less. But this is past the range at which the cartridge has a reasonable level of performance.
If you decide that a 175 SMK launched at 2650 fps has a certain amount of drop range and wind drift at 800 yards, and make that the "cut line", then you can run the ballistic calculator (e.g. JBM online) with other loads or cartridges to see at what distance they have the same drop or wind drift. That will be an approximate point of equivalency.