Ok, so some probably know and/or use the wind correction formula that (I think) uses the 1st digit of the BC
What seems to "work" (or at least line up with my ballistic calculators) is this

[Wind (mph) / BC#  ] x [Range/1000] = mil # wind correction
Out to 500 yd, this is "minute of steel plate", effective to get on target
Past 500, you add .1 to the distance portion.
Using 3 as my 5.56 (77gr smk) number and 4 as my 308 (175gr smk) number, the math works out to within .1 mil or so (close enough for hits on plates)

308 example: 8mph full value wind @ 500 yards
[ 8/4 ] x [ 500/1000 ] = 1.0 mil correction

eg.
video

Question:
Does anyone know the math behind this?  Who/how was this formula derived?

Don’t know the math behind this, but JBM Ballistics predicts O.9 mil correction for the given conditions.   Sounds pretty close to me

What velocity and BC you using for the 308 with JPM?
Im using .5 BC and 2650fps, standard environmentals (59 deg F etc)
I get .6 mil hold @ 500

For MOA calculations, I was taught to multiply the wind speed by the distance/100 (400 yards=4, 550 yards=5.5, etc) and then divide that number by 15 for under 500 yards.  Use 14 for 500-600 yards, 13 for 700-900 yards, 12 for 900-1000 yards and 11 for 1000+ yards.  This formula was originally intended for 308 but works well for 77 grain 5.56 ranges as well.  This calculates for a full value wind.  Divide by 2 or 4 for half or quarter wind values.

Example, at 400 yards with a full value 12 mph wind, you multiply 4 by 12 to get 48.  Divide by 15 to get 3.2.  So your MOA wind hold would be 2.25 since most scopes do 1/4 MOA click adjustments.

Disregard, I had older, my browser was caching values on the screen

Last I checked that would be 48

Good catch.  No wonder I never hit anything.