Originally Posted by Broz
The first wind has the greatest effect on the bullet path. The first wind starts the trajectory off path earlier and it will continue off path from point of aim / to point of impact growing with distance. The last wind drift the bullet encounters will have the least effect. Drift is an equivalent to BC. I have actually seen bullets gain BC as they slow. I do not feel there is a given that a bullet has to loose BC as it slows.
My general experience on the latter point is actually similar.
More or less what I see is that the flat and more rounded nosed bullets gain BC as they slow but that the longer more pointed bullets tend to lose it and the more pointed and streamlined the bullet the more rapid the BC deterioration occurs.
It's also generally seemed to me that the wind has a greater effect at longer ranges which tends to be proved out with the ballistic data.
If you take a given bullet and plot it's wind corrections across a 1,000yds shot by breaking the shot into three separate shots using the calculated velocities at MV-330, 330-660, and 660-1,000 I think with most bullets we use you'll see what I mean.
The following table is provided as a "cheat sheet" that you can tape to your gun.
Your Round 180 gr. 0.5 B.C.
Come UP in MOA 02.91019.933.8
Come UP in Mils 00.82.95.89.8
Wind Drift 05.222.757114.1
Wind Drift in MOA 01.63.66.19.1
Wind Drift in Mils 00.51.11.82.6