How to calculate energy with your shoes on.

BlackShadow · Post by **BlackShadow** » Sun Jun 01, 2008 11:34 pm

Most guys that have a chronograph, don't know an easy way to calculate energy. Most formulas assume a certain level of mathematical knowledge. If you're like me and have to remove your shoes and socks to do math, then here's a simple formula for calculating kinetic energy.

You can do this on a basic calculator and you only have to remember a couple of things. First, any bullet weight over 99 grains gets a .00 before the weight. Any bullet weighing less then 100 grains gets .000 before the weight.

Example:

A 350 grain bullet is entered into the calculator as .00350

A 165 grain bullet is entered into the calculator as .00165

A 55 grain bullet is .00055

This just keeps the calculation from overwhelming a small calculator.

Enter the weight of the bullet as shown.

Multiply it by the velocity in fps

Multiply that number again by the velocity in fps

Multiply that number by .2218 (the magic number)

Now you have the energy in foot pounds.

Example: My .444 pushes a 300 grain bullet at 2450 fps.

.003 x 2450 = 7.35
7.35 x 2450 = 18007.5
18007.5 x .2218 = 3994 f/lbs

Jaguarundi · Post by **Jaguarundi** » Mon Jun 02, 2008 3:10 am

Nice calc equation

!Thanks for posting.

AJMD429 · Post by **AJMD429** » Mon Jun 02, 2008 7:01 am

Good info. Even though some say "energy" doesn't matter regarding hunting lethality, it is STILL a useful number to know, and I think does equate all else being equal. Maybe energy times meplat area or something would be the ideal number?

Jeeps · Post by **Jeeps** » Mon Jun 02, 2008 4:00 pm

Sweet calculation

As far as "energy" goes, I think I've heard of most calculations like TKO and
the plethora of others.

I just think there is a "sweet spot" for each projectile depending on caliber, shape,
weight, construction, velocity, and game being hunted.

Listening to old fanny burbs who have taken many, many game animals is usually the
better way to go. They know what works and will tell you so. Take what they
say and see if it works the same for you.

Practice makes perfect.

AJMD429 · Post by **AJMD429** » Mon Jun 02, 2008 4:10 pm

Jeeps wrote: Listening to old fanny burbs who have taken many, many game animals is usually the better way to go.

How many on this forum did YOU just insult...?

As they say, "Beware the [old] man with but one gun; he likely knows how to use it well..."