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Posted By: Henryseale Ft. Lbs. Energy? - 02/27/20
Does anyone here know the formula for calculating foot pounds of energy for a load? I know it involves the velocity and bullet weight.
Posted By: saddlesore Re: Ft. Lbs. Energy? - 02/27/20
Velocity Squared X Bullet weight/ Divided by 450240

Example.
1200 x 1200 x 150 / 450240=

360000/450240=

479.74 ft lbs
Posted By: memtb Re: Ft. Lbs. Energy? - 02/27/20

Henry, While this isn’t an answer to your question......here’s a link to a very informative website. It gives much info/inside into ft/pounds energy, momentum, Taylor KO values, ect. It may cause you to question what we’ve been led to believe most of our lives! memtb
Posted By: LouisB Re: Ft. Lbs. Energy? - 02/28/20
memtb

If you would be so kind, I would not mind seeing that link myself!
Posted By: memtb Re: Ft. Lbs. Energy? - 02/28/20
Sorry! Damn, I must be getting old.....I thought that I had provided the link! mad I’ll try again! memtb


http://rathcoombe.net/sci-tech/ballistics/wounding.html
Posted By: Border Doc Re: Ft. Lbs. Energy? - 03/01/20

Thanks for the link, memtb.

The "Power Factor" used for Single Action / Cowboy shoots is flawed, but it provides a yard stick kind of standard that is VERY easy to calculate.
Bullet wt in grains X velocity in fps divided by 1000 such as the old .38 Special LEO load of 158 X 850 = 134.3 PF
1,000
The SASS knock-down targets are configured to fall at that level of power. I think the IPSC Power Factor is calculated the same way, with Major and Minor categories.

These formulas are just crunching numbers, not related to real life effectiveness, but I remember seeing the Colorado hunting regulations at one time specififying that 1000 foot-pounds ...or is it properly pounds-feet?...of Kinetic Energy is the minimum for hunting big game. I found a handy table for calculating KE in one of my older Speer books.
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