exactly stubble, but once you have it figured out its pretty easy to build a reliable drop chart, The last one I worked with I did the measuring of the scope heigth, chrony'd the velocity and printed out a chart for an alt of 2800 ft and bar pressure of 29.6.
went shooting and dialed my scope to the chart for 660 yrds, group was 1.5" above POA, went home and tweaked the published BC, and that put it right on.
The bottom line is that you still shot the load to verify the point of impact,something that far too many people never do.Too many people simply look at a published chart,sight the gun in at close range,then go hunting and take longer range shots hoping that the chart is correct for their load and rifle.