# Ft lb of energy needed per lb of animal?

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by trader388, Feb 25, 2004.

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323
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Feb 12, 2004
Is there a standard or maybe average ratio of energy needed to kill per pound of animal? Say 400 ft-lbs minimum to kill a 200 pound white tail. ...so 2 to 1.

So how much is needed for that giant moose or brown bear....how about an elk.

Assume penetration and expansion is not an issue.

2. ### GuestGuest

well , expansion and penitration are an issue that can't be overlookedas abullet kills from hydrostatic shock which is the energy that is transfered to the animal from the bullet. If your shooting a 300Wby with a 200gr solid bullet that doesen't expand at all that bullet is going to zip right through the animal without "dumping" any of it energy which would be alot , but if you shoot that same animal with say a 165gr Ballistic tip out of a 308 , that bullet is going to expand and "dump" more energy into the animal resulting in a quicker kill.
Now if you shoot that same critter with a 22-250 and a 50gr V-max at 4000fps then you probably won't get enough penitration to get into any viatals and kill the animal , yes you will have dumped all of the loads energy but not into the organs.

A bullet kills from either causing such an amout of trauma and shock that the animals organs shut down , or the bullet hits major bone structure and disrupts the centeral nervous system causing systamatic shutdown.

This is what makes controled expansion bullets best for hunting over no expanding solids , but is is possible to have a bullet expand to fast.
And remember Sierra Match Kings are terrible hunting bullets and are dtrictly for shooting at paper

3. ### QuarterboreWell-Known Member

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103
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Jan 31, 2003
I've always suggested using Energy(lbs) thats (4 x the animals weight). Example a 200 pound deer needs 800ft.lbs. energy.

or roughly;
deer: 700-1400lbs. "Energy"
Elk: 1400-2000lbs.
bear: ?? 2500++

of course there is lots of varibles but this is a good rule of thumb.
nullnull

4. ### Michael EicheleWell-Known Member

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Jan 6, 2003
308WIN put it well. You have to remember that some animals flesh is denser than others. Like grizzly bears being the densest. I prefer about 2 times their body weight minimum. or for the biggest of them 3000 FPE impact, not muzzle energy. For elk I prefer 1500 minimum for impact energy. Dall sheep I only need 500 FPE. Deer as a whole I like 1000 FPE. Each animal not only have different densities but differant bone structures as well. Also, many have differant drives and will power to survive. Moose are bigger than elk by far, yet moose are easy to kill compared to elk. Moose are more like mule deer, they walk about 20 paces after being hit and thats it.

Regards,

5. ### *WyoWhisper*Guest

You guys are pretty much right on the money with what I would answer..

Whitetail 600 lbs+
Muledeer 800 lbs+
Elk 1500 lbs+

Bear depends on the species...

I do know that you need a 1/2" wound channel minimum..

6. ### Jay KyleWell-Known Member

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Jan 6, 2002
Hard to nail it down to any specific weight, but a 'rule of thumb' I tend to use is the Optimal Game Weight formula. It's not perfect but it's not bad either.

AB