Originally Posted by AJ Peacock
Using the load info will not get you accurate enough for much, as different rifles behave much differently.
If you have a drop chart and all the environmental conditions, you can work backward and get a fair guess with one of the ballistic programs.
For example my 7mm Rem Mag, shooting 160gr Accubonds is sighted in at 200yds, the sight height is 1.5" and I have to crank 14.75 moa up to hit at 800yds when at 7480' elevation. By playing around with the program I can see that I am around 3000fps.
My chrono tells me That I average 3015.
Your best bet is to spend a couple hundred $$'s on a good chrono and use it. It will save it's cost in ammo over the next few years.
Before I could afford a chronograph I did about the same thing. I would shoot 5 rounds (Minimum) at each distance. 100,200,300,400,500,600,and on some rifles 1000 yards
using a target large enough to get all of the groups on it.(I used the brown rapping paper
on a 4" roll 4 to 6 ft tall.
Then I placed a contrasting aiming point placed at 12 o'clock high and aimed at it for each
group of shots at each distance.
When I was through I found the center point of each group at that distance and used the
drop to make my chart.
Then using the reloading manual from the bullet manufacturer I matched the drop to the
ballistic tables for that bullet weight and it got me close to the average velocity.
And after many years I finally broke down and bought a chronograph and boy was it easier.
And for working up loads much faster.
J E CUSTOM