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The problem I see with bullet manufacturers is that they don't give a shit because the mathematical models they use don't differentiate between bullet designs like wadcutter,flat base,spitzer,round nose semi Spitzer etc.etc.etc.
They assume one drag function and run with it.
G1&G7 just happen to be the most popular rounds that's why the data for G2,G5,G6,G8,GL is hard to come by.
Just figured I throw this simple graph in.
Interesting! Thanks!
I am going to guess that both peak in the 1000-1500 FPF range because if the turbulence during the sub to supersonic transition?
Is there any insight you can offer would be appreciated. Is there something else causing that spike in drag that you are aware of?
It's a shity,low resolution picture.
Two.
So,
To do a table right,
If a person had a list of g7 bc's at diffrent velocities, would they take an average of them, or use the one at the velocity/longest range they intend to shoot, providing the velocity is still supersonic,( mach 1.2 I think I saw somewhere) then verify by shots on targets at known ranges? Or put whatever bc is given either g1 or g7, and a measured muzzle velocity, and adjust from there, or are the diffrences not enough to be concerned with at NRA mid to long range distances...
I don't have anything capable of reaching farther than that..
Jbm ballistics has the g7 data in their library listed as (litz) otherwise it is g1 I think...
The bullet data base has some listed with velocities but does not make a distinction of which model it Is..
It may be a moot point with my shooting skills,or lack of, but I would like to know the proper way to derive a drop/driftc chart based on best available info..
Other wise I have been within reason and a couple clicks with a measured muzzle velocity, and a simple bc.. but that has been at short ranges
As you can see.
Ok, I see and understand...
If you had these pills.....
0.224 77 gr smk
O.224 80 gr smk
O.243 75 gr hornady v max
O.243 87 gr hornady v max
O.308 168 gr hornady match
0.308 175 gr smk
And measured muzzle velocity, what data would you use, and how would you build a drop/ drift chart?
All are diffrent length barrels with known twist rates..
Chrono data would be an average of 10 shots, more if need be, temperature, and wind readings recorded at muzzle, shots taken at 100 yds.
Three.
Good enough answer for me...
Just something I have always wanted to know..