Math formulas

[Zocktan]

P =(1.044*V -Ln (0.194*L/d) -0.212 ) * L

i've got some questions tp this formula!
1. what does the constants discribe?
2- "-ln" because the projectile becomes slower, but why L/d?

[MarkSheppard]

Holy @#$%, Am I in the right forum?

Yes you are.

This looks like a Mensa club meeting or rocket science forum. This is too much for my Infantry Grunt brain to handle!

It's actually a quite easy formula to understand, it's basic algebra; unlike a lot of other formulaes out there

[MarkSheppard]

Actually, you got the formula wrong.

It's really

Anderson:
P = 1.044 x V - 0.194 x Ln(L/D) - 0.212 * L

V: velocity (Km/sec)
L: length of the penetrating rod (mm)
D: diameter (mm)
P: Penetration

HOW TO DO IT:

Now to provide the numbers:

V = 0.81 (810 m/s) = Velocity
L = 370.05 = Length of Penetrator (mm)
D = 88 = Diameter of Penetrator (mm)

Roughly that of a German 88mm L56 shell.

So we've got the following equation now:

1.044 x 0.81 - 0.194 x Ln(370.05/88) - 0.212

First thing first, we need to solve the Logarithimic problem; excel is great for those of us who did not pay attention in Math; it has a Logarithm function.

370/88 in Logarithimic is: 1.4363

So now the Formula is:

1.044 x 0.81 - 0.194 x 1.4363 - 0.212 * 370.05

Something that you can solve with basic infantryman math.

That formula results in

131.36mm penetration.

That's actually quite close to the actual performance of the 88mm L56 Panzergranate 39 round; which was 120mm of armor at 30 degrees (139mm total) at 100m.