RE: What energies are required for clean kills?
 

Problem with energy is alot of gunwriters don't know what it is. I read in G&A once that energy is false and if it was true, then hitting a deer would be like hitting something with a car and make the deer fly in the air. What was was mistaken about is energy of the car. If the steel plate was hardest material in the universe and did not deform any at all. And the bullet was indestructable and did not change shape in any way when hit, then at that moment when it hit the target, there would be 2000ft-lbs of energy at that instance. But the change in bullet shape uses up alot of energy. The decelleration when entering the deer uses up considerable amount of energy.

RE: What energies are required for clean kills?
 

I have that book by Bob Hagel. Great reading!

RE: What energies are required for clean kills?
 

if you want to rate your bullet by its energy fine, But a .223 is the smallest centerfire allowed for deer in most states also has a low bullet energy a 60 grain 223 only has about 1200 ft lbs at the muzzle and only about 900 ft lbs at 100 yards. But if that .223 is placed right it will kill a deer just as good as a 30-06, Basically what I am saying bullet energy doesnt matter when your shot is placed right. A friends grandfather that I used to hunt with uses a 25-20 in a old winchester model 94 at 100 yards the bullet has only about 300 ft lbs of energy I watched that old man cleanly kill many deer with that 25-20 over the 4 years I've hunted with him and his grandson.

RE: What energies are required for clean kills?
 

The thing you have to remember about energy is that it doesn't mean anything BY ITS SELF! 3000 ft/lbs is alot of energy if its in a 250gr .338 bullet, its not if its in a 200lb cannon ball. Another misconception is that caliber doesnt matter. if you put 3000 ft/lbs of energy into a projectile that is ,say 1/100 the size of a sewing needle weight and caliber both(assumeing it's unbreakable). it could pass through your forhead and not drop you. Thats exactly what radiation is, it only hurts you when you get billions of them at once and get a "shotgun" effect. Energy means alot when coupled w/ 1)bullet diameter 2)bullet construction. DM - First I'm not hacking on your 7mag, its a fine caliber, but you need to compare apples to apples. You cant compare 300win-180gr- $12/box factory loads to 7mmrem mag w/ 175gr nosler partitions. 1) bullet weights - 180gr is avg weight for 300, 175 is heavy for caliber in 7mm 2)also nosler partitions are a premium bullet, designed for big game. For a real comparisn you should have partitions in both and about 225 gr bullet in the 300(heavy for caliber). I gaurantee with ALL things being equal the 300win will out penetrate the 7mag. Having said that, If you have handloaded your 7mag as we mentioned before you may be right that your as gunned up as the guy who goes out w cheapo factory ammo in a 300, but that guy does have more gun than if he had a 7mag w/ cheapo ammo. As for 7mm and griz... I dont shoot em , so I'd ask some guides who see dozens of em shot each year.

RE: What energies are required for clean kills?
 

The excerpt from Chuck Hawkes essentially stated that KE is only useful when comparing similar things, and that it is misleading when comparing dissimilar things.

So then, there is no answer to the original question on what KE is required to produce clean kills. More info. is required. You neeed to know bullet caliber and design (weight, construction, etc.).

I have shot deer with a 45/70, loaded with rem. 300 gr JHP bullets driven to roughly 2000 fps. One smallish 6 pointer trotted on past while I unloaded on him, and only fell down because my last shot was a neck shot as he was going straight away. I hit the deer 4 times in all, twice in the ribs. There is no way that deer should have soaked up all that KE. But the bullets basically failed, as the jackets were not constructed heavily enough for that velocity. I didn't get one pass-through. KE is in fact the bullet's potential to do work, but other things contribute to it's actual ability to do the work correctly.

RE: What energies are required for clean kills?
 

One of the things one should note, as pointed out by oldelkhunter here in his story about the guy holding the plate that was shot with the .458, is that these "foot-pounds of energy" ("ONE FOOT-POUND MOVES A POUND OF MATTER ONE FOOT") aren't REALLY really foot-pounds at all! If it were, "5000 foot pounds" would move a 100-pound animal 50 feet from where it was when hit! It doesn't.

As pointed out by Briman, "In reality, the bullet doesn't hit an animal with anymore force than the stock of a rifle hits your shoulder." So what does this figure do for us? It allows a kind of comparison between calibers which are using bullets of identical construction that are travelling at comparable velocities. When the velocities of calibers being compared differ significantly, such a comparison becomes invalid, because projectile behavior changes so much. For example, a shotgun slug or ML bullet travelling in the range of 1000 to 1500 FPS kills by hemorrhage, just like a broadhead arrow, and has little shock effect. Hence an animal shot with one will keep travelling until it bleeds out, unless some critical structure like a leg, shoulder, or spine is destroyed, preventing it from travelling. When velocity moves into the 2500+ FPS range, things seem to change, and animals shot with bullets going much faster than 2500 FPS usually travel a lot shorter distance from where they are hit, if the hit is anywhere near a vital spot.

I get a kick out of people who maintain "you must have a minimum of X number of foot pounds to kill a Y animal," etc., because such statemewnts are patently ridiculous. They totally ignore all the other significant variables in the killing power equation!

RE: What energies are required for clean kills?
 

Brimans assertion that the bullet only hits as hard as the stock hits your shoulder is as wrong as opening a brothel in a church. There are alot of ways that the energy you get hit w/ differs from what the animal gets hit w/. Gases vent preasure, muzzle flip, heat, noise, brass forming, all of these plus probably a thousand more all disipate energy in different ways, it also ignores the main point, surface area over which the force is applied. If you dont believe me take 22lr bolt or single shot, it wont kick at all right? drill the stock and insert a 1/4 dowl(slightly smaller than a pencil), put the dowl up to your nose, put the gun on a rest so that nothing but your nose(through the dowl) recieves the recoil. Tell me what happens. Name and address withheld to protect my hide after you try this.:D

RE: What energies are required for clean kills?
 

You can have a stock that is only a 1/4" dowel or even a needle- it will still hit you just as hard as a regular stock, though penetration will me much greater.

I'll reword my stance- a bullet hits with LESS force than the stock of a gun as it will loose momentum from heat, friction, wind resistance, etc, not to mention that some of the recoil you feel is nothing more than the mass of the gasses created by the burnt powder ejecting from the gun which do not hit the target at all.

RE: What energies are required for clean kills?
 

Mike, in response to your colorful assertion, let me refer you to Newton's Third Law of Motion.

RE: What energies are required for clean kills?
 

Eldeguello in responce to your post, let me point you to Newtons laws also. Equal and opposite reaction is used to a point here too. Not true that 5000ft-lbs would they a deer 50ft. For that assertion, no energy would be used or lost with the crushing of the bullet. No energy would be lost entering or penetrating the deer. The deer would have to be infinately hard and so would the bullet. Misusing physics just a tad here. You won't believe how much energy is lost just from the deformation of the bullet. Try a test. Get two pool balls, and smack one against another at rest. See the distance moved. Now put a 1/4 cotton on the one to smack it, do the same thing. Enormous amount of energy lost. Also pool balls are close to ideal as a person can reasonably get. If they were infinately hard, the effect would be ten fold as they deform also.