How to figure out my ammo's "Math Constant"

[Heimdall]

In the old USMC windage formula they use a math constant of 15 to 500 yards, then it changes for distance. I have seen different numbers for different loadings of 30 caliber ammo.

Any way, the question I have is what is the formula to find this constant number? I shoot the 30-06, 7.62x54, and 308 so this could be quite helpful info since this formula works for the 30 caliber.

 

[kraigWY]

Re: How to figure out my ammo's "Math Constant"

Corrections needed for wind is

R x V / C = A

R = range in 100s of yards

V = wind Speed

C = Constant.

A = adjustment or correction in moa

So at 600 yards in a 10 mph wind / constant its

6 x 10 / 15 = 4 (moa corrections)

You want to find the constant. If any two are known you can find the other

Use R x V / A = C

In the above example

6 x 10 / 4 = 15

From your balistic chart you see that at 600 yards you need a 4 MOA correction at in a 10 mph wind.

With that, you get your constant.

 

[Heimdall]

Re: How to figure out my ammo's "Math Constant"

Thank you.