Good luck estimating longer ranges well enough without a LRF. If you guess 500 and the actual is 550, you'll be off on elevation by almost a foot. It gets worse the longer the range.

The development of the LRF is the single most important development in long range shooting, even more so than the telescopic sight. Without accurate range estimation, the most accurate rifle in the world topped by the best glass is useless for making first round hits at extended ranges.