there are lots of programs available for creating an elevation chart. jbm is but one of them.
even if you dont have access to a chronagraph for measuring your velocity you can still fudge your way thru it.
fact is since many chronagraph units lie about velocity you might be fudging anyway.
so just pick a number you think is close to your velocity and enter the information.
if your actual shooting requires adding more elevation than the chart your velocity input was too high and you need to back off on the number. if it required less adjustment to reach the target your velocity input number was low.
within a few tries you can create an elevation chart that will be right for that gun and load.
as for clicks vs minits remember that one quarter minit click is one quarter of a minit.
its just that simple.
50 years ago there werent any scopes with the turrets available today.
fact is there werent many scopes period.
at least usefull for this kind of stuff.
so about everybody counted clicks since there were few alternatives.
now for the record, not many were dumb enough to count off say 80 clicks.
one rev of the dial might mean 50 and a rev and a half ment 75.
we could get the other 5 by only removing one glove.
sort of the same as adding a minit and a quarter.
so it went pretty well even though many today sneer at the idea of counting clicks.