Free is the key word but that's all you get. I don't really use the other things like TKO, etc... anyway.
http://www.appbrain.com/app/bullet-energy-calculator-free/cornale.EnergyCalculator
Strelok has energy figures as well as external ballistics.
I just remember the energy formula...the crude one. (Weight(grains) * Velocity (fps) * Velocity (fps))/450450
So, for a 200 gr at 1200 fps:
200*1200*1200/450450 = 639
Quote from: sqlbullet on August 04 2012 09:19:46 AM MDT
Strelok has energy figures as well as external ballistics.
I just remember the energy formula...the crude one. (Weight(grains) * Velocity (fps) * Velocity (fps))/450450
So, for a 200 gr at 1200 fps:
200*1200*1200/450450 = 639
That should be (Weight(grains) * Velocity (fps) * Velocity (fps))/
450400450400, like the old elephant round. Easy for me to remember, because my dad carried a 450/400 double rifle in Africa, and I grew up on stories about it.
My App says sqlbullet's formula is correct.
I have seen values from 450400-450450 different places. I think I read the actual most accurate is 450435.
E = 1/2mv^2 /(7000 * 32.1739ft^2/s^2)
The 7000 is to get grains to lbs, and the 32.1739 is to normalize for local gravity. 7000*32.1739*2, since we have to divide by two is 450434.6.
The total spread between 450400 and 450450 for a 200 grain bullet at 1200 fps is 0.07 ft-lbs.
Even looking at 300 win mag numbers of a 200 grain bullet at 3000 fps, the different is only 0.44 lbs-ft.
So, whatever number is easy for you to remember in that range will get you to the nearest ft-lb.
You are right. My Speer reloading manual says 450400.