Can't you zero an AR for 25, and also be on at 200? Because of the distance of the sights above the bore, the bullet is travelling up as it crosses the 25yd line, then back down through the line again at 200. If you figure your target as a 6" circle, that's probably a 250yd point blank range. I shoot only at paper and steel, but I know guys who are shooting at 12" targets from 30 feet to 300 yards and not adjusting their sights.
