coipied and pasted



"The killing power of a bullet in flight depends entirely upon the average size of the wound it makes in the animal, and upon nothing else. The size of the wound in turn depends upon the size, weight, construction, and shape of the bullet, and the velocity with which it strikes, and upon no other details. ... We frequently see it stated that the killing power of a cartridge depends upon its energy, and tables of the properties of cartridges often give the energy of each. Now energy depends upon the weight of the bullet times its velocity, and on nothing else, and thus can have only a very distant bearing on our subject." (Townsend Whelen, The Hunting Rifle, Stackpole Sons, 1940, pg. 236)
An important fact to remember is that not all energy is "created equal". What this ultimately means is that a kinetic energy value used as a measure or threshold for lethality is practically meaningless. The character of the work done by a certain quantity of kinetic energy will be dependent upon the mass, construction and velocity of the projectile. In other words, 1000 ft-lbs of kinetic energy generated by a slow-moving rock is not as lethal as that of a bullet. Furthermore, the damage actually caused by a lesser amount of kinetic energy may easily exceed that caused by a greater quantity of kinetic energy! Expressed differently, kinetic energy has "quality" as well as "quantity". This is easier to understand in terms of heat energy, which has temperature (degrees F or C) as well as quantity (BTUs or Joules). Kinetic energy is governed by similar laws.
As further evidence of this fact, observe that when terminal ballistic experiments are scaled the velocity is held constant. Kinetic energy, mass and the dimensions are scaled, but velocity is not. In like manner pure water at standard pressure boils at 100° C, regardless of quantity. A small amount of water does not boil at a lower temperature than a larger amount. The heat required to bring a quantity of water to a boil is directly proportional to the mass of the water (just as the kinetic energy is proportional to the volume of displacement by a bullet), but the character of the work done on the water by that heat energy is determined by the temperature it produces. It is velocity, not kinetic energy, which is the quantity of greatest interest in the terminal ballistics of small arms.

Regardless of how it's applied, it's still the kinetic energy that does the work. No kinetic energy, no hole. It just happens that the bullet is a better conveyor of kinetic energy to a target than a 1lb bag of gel because it concentrates said energy into a smaller area and therefore more destructive to tissue. If kinetic energy doesn't have anything to do with killing, what happens if we take it away (i.e. slow the velocity to zero)? Yep, a bullet that isn't moving doesn't kill, does it? To make the bullet lethal it must be moving fast enough, and when we make the bullet move we are adding the kinetic energy that the bullet needs to do its damage to its target. No KE = no wound = no death. You've hung up on HOW the KE is applied (the vehicle), I'm merely stating that it IS the KE that does the job. The amount of KE that's required depends on the size, shape and consistency of the projectile, but it's still ultimately the KE that does the damage.

Mike

sigh........

Jeff, this was so much more entertaining at sgw. I have zero experience with the sabot slugs that you use, but a 12 gauge 2 3/4" 1 ounce rifled slug will kill anything that you can hit with it. I never lost a deer that was hit with one, huge holes and lots of blood.

Hey Centaur,

I was trying not to be specific in my question so as not to influence the answer. However, as you can see...despite the fact that I gave a pretty specific description of the exact projectile and firearm type I was interested in opinions on, (20 sabot slug)...some folks still have to fly off into the "it all depends on this and that"....(We know that, which is exacly why I gave a general "this and that" to base your answer on.)

Either way, this thread is pretty much confirming that most people never even think about the answer before pulling the trigger. (Not that I am saying they have to, as long as they some other thoughts on the issues involved.)

Good to hear from you Centaur!
JC

Kinetic energy alone means nothing.

What kills the animal is how the object transfers the KE to the animal and the amount of time it takes to transfer that energy.

It's like the old saying... "Speed kills".
No it doesn't.
The rate at which speed changes kills.


To answer the question the minimum amount of KE depends on the bullet being used. A suitable bullet could be coming from a 223 Remington or a 45/70.

Yes the number would change if we were talking about a 20ga slug vs a lighter weight lesser constructed bullet.

I would want about 500 foot pounds of KE from a rifled 20ga slug on the deer at about 100 yards. Which the 20ga slug would have in spades.

I'm sure glad I don't have to worry or think about any of this 20 gauge kinetic energy this and that.

I shoot a 12 gauge!

Hey JC - how ya been?

Been good Matt,

To make a long story short...I started a dedicated slug forum on another site a few years back...and to this day it still takes up a good deal of my time.

This thread was posted to get some info on a particular issue but as you can see most replies here didn't even seem to adress the subject. Although admittedly, it is not really a subject most shooters are very well versed in.

Either way it is good to hear from you...

JC

(BTW...For reference, noted slug gun author Dave Henderson apparently states that 900 ft lbs is the general minimum in his opinion. While I personally stick with the general range around 1000ft lbs simply because there are almost no situations where I can not achieve that power with my slug guns within an ethical distance. Within 125 yds that is no problem with my 20ga and if I am planning on shooting farther than that my 12 ga is more than adequate well past the range of any ethical distances it should be shot....outside of that, there is really no reason to go any lower)

Yeah I noticed the lack of addressing the question of minimum KE also.

Myself I go with 800 as my minimum but I am sure much less will do the trick in the heart.

BTW we'll be zeroing in a scope on yet another H&R this weekend.

I thougt about my answer before posting, that's why I didn't...