What you tryed to do IS NOT WORKING IN THE FIELD.
I use the same like others guys, 2 power in my scope 16X for shoots past 800yards and 10x in close range.
I already develope a drop chart for holdovers in MILS and it is stick on my stock, and another one in my inside cover cap for scope.
K.I.S. this is the way to go (Kip IT SIMPLE).
I develop my self a excel file for my PALM, where i just insert all the variables and I got the holdovers in mils or click for X power scope.
If you need it shoot me one email. THE EXCELL FILE USED ALSO THE SLOPE CORRETION, tem, elev, wind, etc... all variables from EXbal.