I have read that for the Power(energy) the constant to use is the number '450411' but i learned in the past when i was for Many years with the 1GVP(now SFG), that it was '450240' i know the result isn't a big difference. But if want to know the exact Muzzle powerenergy i think it's interesting to know wich one is best to use my friends.
For example for my favorite Windrunner .338cal model98(nice to shoot around 1500yds or even 1500m: muzzlevelocity 2950fps, 250gr, BC 0.597, ImpactVelocity@1000yds 1642fps, site height 2.12" =Formula 250 x 2950² / '450411' = 4830.311 Power or MuzzleEnergy, and as i learned 250 x 2950² / '450240' = 4832.145 Power or MuzzleEnergy !
Altough if i calculate the Muzzle energy with my downloaded PointBlanckBallistic-software, then i got a complete other result after i gave in the 250gr & 2950fps numbers = result in PointBlanck 6551.422(FPE). So what the heck is that REAL 'constant' then? ?
I also use regularly the PointBlank-ballistic software,mostly to compare if my estimations still being good, this software is very good. But mostly i only calculate everything the way that i've learned it in the past with 1GVP, on my calculator. No wind or forecast software. Fieldcraft & sight estimations only. That's why i like to use MilDot-systems also.
So, as you can see the result with both 'constants' is not a big difference , but for some specific calculations it can be necessary to know the exact 'constant'-number. Certainly to concern is the big difference in the MuzzleEnergy-result in PointBlanck in relation to my normal(without software)calculations.
Thx in front to everyone and those who like to learn/read about external ballistics too,