Shock/energy/knockdown

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Boogershooter

New member
Back in (colludge) I studied this in physics class. My professor was a hunter too so we both did some research. There are several Dr's and universities that did extensive tests with pigs. They did this by shooting dead pigs n the ham/hind quarters with pistols. They put pressure sensors in the lungs, heart, brain, and spine. They found that at just 500 lbs of transfered energy would disrupts a pigs functions. Bust blood vessels n the lungs. Separate the spine just a bit. Cause enough disruption in the brain to stun the pigs. They found at 800 lbs of transferable energy the shock wave thru the fluids and tissue would b fatal. Actually breaking the spine, collapsing the lungs, and causing the heart to stop. Now remember this is measured from a shot to the ham. Image if the bullet impact was in the shoulder which is closer to the brain, lungs, and heart. If this study was true then surely any modern rifle with a bullet transferring that much energy to a animal should be fatal almost everytime. But we all know this isn't the case. I'm interested in hearing some others points of views or if anybody else has studied this please share what you know.
 
There have been myriad attempts to quantify energy transfer, knock-down power, killing power, etc, over the past century. All of them had had their adherents, some still do (e.g.- what is a "foot-pound" of kinetic energy? If you do the stoichiometry on the units, it is a ft/lbs, a nonsense unit), but most fail to explain even the simplest of events, like "how do we kill an animal?" Lots and lots of formulas for energy calculation (energy doesn't kill a game animal), force of impact per unit of frontal area of the bullet (another one of those things that sounded like a good idea but gives results like "a 44-40 kills better than a 243 because our formula shows it to be so"). Ultimately, you gotta go kill something to show that it can be done. And I'm not too sure about bursting blood vessels and all that, a 30-30 is still a good killer and a 300 RUM will ruin too much meat.
 
Put a hole in any animals lungs and it will die very shortly. It doesn't matter whether an arrow with less than 200 ft lbs does the job or a rifle bullet with over 2000 ft lbs hits it.

Bullets that cause the most damage to internal organs drop animals faster than bullets that do less damage. There are lots of factors that determine this and energy is one of them. But not the only factor. It is a complex issue that cannot be explained in simple terms. You also have to consider bullet construction, diameter, and bullet speed.

A lot of folks will discount energy numbers as being useless. I don't believe that. If you understand the other factors involved energy numbers can be used to predict how much damage a bullet will do when it hits an animal.

As long as you compare bullets of similar construction, and diameter the one with the most energy will do the most damage. But energy numbers are biased toward more speed which gives small caliber ultra fast bullets a mathematical advantage over larger slower bullets which doesn't always prove to be the case in the real world.

Traditionally 500 ft lbs has been described as the minimum one should want for deer sized game with 1000 ft lbs considered about ideal. Around 1500 ft lbs for elk size game. If you are comparing modern rifle cartridges with bullets of the appropriate construction I find those numbers pretty accurate. If you choose the wrong bullet for the job, then the energy numbers can be very inaccurate.

a 30-30 is still a good killer and a 300 RUM will ruin too much meat.
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I think that is more a matter of bullet construction and the range the animal was shot. The same bullet from the 300 RUM is traveling at about the same speed at 400-500 yards as the 30-30 at the muzzle. And an animal shot but not recovered ruins a lot more meat.
 
Kinetic energy is not conserved in a collision and yet is a favorite number for those who tout high velocity bullets. Since KE increases by the square of the velocity, it is a lot easier to inflate the numbers. Momentum is conserved in a collision, momentum is mass times velocity. It is a lot harder to inflate momentum with meaningless velocity increases.

Stopping power has been argued and studied ad nauseam. After enough small game hunting, I am getting into the Fackler camp. If it bleeds, enough blood loss will kill it. Blood loss is a 100% kill mechanism and anything that contributes to blood loss is good, from a killing standpoint. I am therefore of the opinion that a big, wide, hole is better than a smaller hole. From what I have read in Fackler's documents, he considered wound crush space and hole through length as primary killing mechanisms, and that is something I agree with. The bigger the hole, the more likely a major organ or vessel is likely to be cut. If you get lucky, you hit something like a spine, or brain, that will shut down the nervous system. The nervous system is pretty well protected by boney structures. But even shots into bone won't get an immediate kill if the recipient does not bleed out quickly.

People have forgotten the killing capacity of older bladed/percussion weapons. Firearms provide killing power at distance, but something like a halberd, two handed sword, mace or war hammer, are devastating close up. Hand held weapons provide much more transferable momentum than small arms. A hit on the head with a percussion weapon, such as mace or war hammer, will totally crush a skull. I have read a number of accounts where British troopers cut people in half with their one handed swords. A foot long cut into a person causes severe trauma, even thrusts cause massive bleeding.
 
boogershooter said:
My professor was a hunter too so we both did some research.... They found at 800 lbs of transferable energy the shock wave thru the fluids and tissue would b fatal. Actually breaking the spine, collapsing the lungs, and causing the heart to stop.
Click to expand...

You guys might want to go back and do a little more research. By your findings a hit by about ANY rifle bullet bigger than a .22 rimfire would be fatal due to the shock wave.

Doesn't work that way in the real world.

EDIT: Sorry, I quit reading your post after the quote above. Didn't waste any time reading the rest. It was just pointed out to me that you disagreed with the above quote later in your post.
 
I disagree with most of the stuff I read or hear. There are always exceptions. In the research we did there was so many contradictions even in the reports of the dr's. To me there is a difference between knockdown power and tissue destroying power. Which kills best will always b a debate. Shooting a piece of metal and shooting a piece of meat isn't a good comparison. But at the end of the day a good shot thru the vitals will always be a fatal shot. I love the arguments of a bigger diameter bullet punching a big hole vs a small diameter bullet causing a bigger wound channel thru velocity. I'm a 30 Cal fan but when I go to the quarter bores or smaller I have to pick the higher velocity cartridges like the 25-06 or 257 weatherby. I must point out that the first few dozen deer I killed as a young whooper snapper were with a 243 and 30-30.
 
Just wanted to hear other people's opinions and beliefs on the subject figuring it might help a few others on here. I do appreciate the responses. Most of us on here are set in our beliefs and nobody is gona change that. Wouldn't it be a boring world if we all drove the same make, model, and color truck? If we all shot the same gun, caliber, scope, and bullets then we couldn't sit back and say look at that guy, he's a idiot for shooting that, I'm smart because I use this and it's better than his.
 
Failing a CNS impact (or peripheral CNS effect from nearby exploding tissue),
"knockdown" is a misnomer -- Hollywood notwithstanding.

"Killing Power" is, however, directly relatable to energy transfer in destruction
of vital organs. And that depends on a witch's brew of mass/penetration/bullet-design/-
expansion/V-squared/what-it-hits first, etc, etc.

Just how "immediate" the kill is another matter altogether. We've seen both men and
animals survive long enough to run 100's of yards and or kill you the shooter -- all the
while in which the heart is virtually exploded and they are literally running/walking dead
their feet.

Faster is better -- maybe
Heavier is better -- maybe
Bigger Diameter is better -- maybe

It's a hellacious systems problem with a lot of Chaos Theory thrown in.
(But you can load the dice) :rolleyes:
 
I'm not a physics major. In reality I know nothing about physics.

I've shot a lot of critters, and seen a lot of critters shot.

I've seen more then enough people shot and have attended autopsies.

I've studies animals and there nervous systems. I've watched untold hunting shows and watched animals reactions after being hit.

The first thing you can paste in your hat and take to the bank:

NO TWO SAME ANIMAMALS SHOT WILL THE SAME BULLET WILL REACT THE SAME WAY. NO TWO EXACT BULLETS HITTING THE SAME ANIMAL WILL REACT THE SAME WAY.

Energy works sometimes

Bullet fragmentation works some times

Heavy bullets work some times

Light bullets work some times

Nothing works each and every time.

All we have is theory.

Deer/antelope/elk type animals have a unique nervous system. The more you disrupt that nervous system, the quicker the kill.

To do that, you need a bullet hat fragments and sends pieces of bullet throughout the heart lung area disrupting the nervous system creating shock.

A large heavy bullet should expand, pass through leaving an exit wound where the animal bleeds out, and dies slower then above. Bows work this way, they pass through causing bleeding.

Bear/hogs have a different system. They don't have the nervous system of he deer type animals. Therefore the fragmenting bullet wont do the damage needed. You need a heavy, slower moving expanding bullet that leaves a large bullet path.

Light fragmenting bullets need velocity to work, (Berger engineers told me that their bullets need about 1800 fps to operate effectively.

Heavy soft point large diameter bullets don't require hyper velocity to do their job.

Again, this is all theory, but makes since.

I believe you need to pick your bullet for the game you are hunting, and you need to adjust your velocity for the distance you are hunting.

Regardless you wont see the same results shooting the same bullet at the same animal in real life.

Watch the hunting shows on the Outdoor channels to see. Very few animals are DRT when shot, regardless of what you shoot them with.

But like everything else, there are exceptions to every rule. But I don't live my life hoping for exceptions.
 
I've shot hundreds of deer. Started with a 35 Remington, went to a 270, then a 260, but have used 308, 30-06, 223, and 220 Swift. I shot enough deer with the 220 Swift to decide that it was not a good deer caliber. You could argue that it was a bullet issue and not a caliber issue, but even if you are right, it's still a marginal caliber for the job. Because of bullet options these days, I do believe that the 223 is better for deer than the 220. As for the rest of the calibers mentioned, the larger the bore diameter (generally speaking), the better deer killer it was. Still, the 270, in my view, was the best DRT deer killer, due to a good bullet moving very fast. The 260 seems almost as good, and the 308 and 30-06 did a fine job. The 35 Remington did an absolutely great job at killing deer. Very few were DRT, but if I hit the lungs the deer was just a short walk away.

Penetration and blood trail. The 35 rules the roost of the guns I've hunted with. Always an exit, with a blood trail that could be followed by Stevie Wonder. The 270 most always had a good exit. So did the 308 and 30-06. The 260 gives a good exit with bullet weights of 120 and above. I rarely ever got an exit with the 220, even with bullets that weren't solely varmint bullets. I don't have a lot of personal data with the 223 on deer, but have shot a number of hogs with it. Use a good bullet and I think it'll do a decent job, though that caliber won't ever be the best for blood trailing.

As for knockdown power, I can't remember a deer that was actually knocked down by the bullet. Drop dead, yes, but blown sideways, no.

I want to place the bullet well, and I want it to exit and leave a good blood trail. Sometimes, no matter what you shoot them with, they run. Gotta have a good blood trail. And lung blood, being bright and frothy, is the easiest to track. When I was younger, I could track a lizard across a dry rock, but nowadays I need something easier to follow.
 
he first thing you can paste in your hat and take to the bank:

NO TWO SAME ANIMAMALS SHOT WILL THE SAME BULLET WILL REACT THE SAME WAY. NO TWO EXACT BULLETS HITTING THE SAME ANIMAL WILL REACT THE SAME WAY.

Energy works sometimes

Bullet fragmentation works some times

Heavy bullets work some times

Light bullets work some times

Nothing works each and every time.

i agree with kraigwy. even tho i have shot and seen shot, deer and black bear. some went right down, while others have run a few feet to 150 yards.
 
jmr40, PO Ackley and a friend went after a large mule deer .Days later they got it .Careful autopsy showed that it had been hit at two different times and survived !!
Other factors like secondary projectiles such as bone chips can go through and seriously damage an animal without 'shacking' the animal.
Penetrate into and do damage to vital organs --that's what is needed !
 
My point exactly. Hunting wild critters with different sizes, standing positions, different angles, different fat contents and temperatures. Nothing in the hunting world is predictable as much as we would like it to be. I've shot enough deer and hogs that I have picked my favorites. Reason they were chosen is because they were the most consistent. A good shot thru the vitals is always deadly and there's no such thing as the perfect caliber or bullet that will kill them everytime with a bad shot. Thanks for the reply's gentlemen.
 
Shooting dead animals is not a good representation of a live animal. Live flesh is more elastic and will stretch rather than tear. Ballistic gelatin is a little bit closer in some ways because (as I'm told) it's essentially rehydrated flesh and has some of the same elasticity of a live animal. Dead flesh when shot will show very impressive looking wounds, but you will get a lot more disruption on a dead animal compared with a live one and that can be misleading.
 
It's really more of a possible/probable proposition, Dr Michael Courtney probably has the best research on the subject but in short you need about 500 psi of wound pressure for remote wounding to be possible and over 1000 psi it's probable.
 
The test was bogus. When the Kennedy investigation was going on, cadavers were used (If I remember correctly, at the Proving Grounds) on the first try to duplicate the original bullet paths. It did not work out. They had to move on to live animals (Goats, I think). Apparently the hydraulic shock was not duplicated in dead meat.
 
Quite possible the Kennedy test was an attempt to make the results fit the incident.
Showing the rear shooter being the lone gun man. That theory is doubted by many.
Try Google XP100 / Kennedy.
Things that make ya go hmmm.
 
Biology and anatomy are not easily quantifiable as constants.

Remember the old joke about the chicken farmer who told a physics student he had a problem with his birds? The physics student thought about it for a few weeks then came back and said, "Well, I've got an answer to your bird problem, but it only works for spherical chickens in a vacuum." ?

Trying to use physics to describe biology is a losing proposition.

In biology, death comes from a lack of blood flowing to keep the brain alive. You can do this by destroying the heart and lungs, and the animal will die from blood loss (lack of oxygen to the brain). You can do this with a brain or spine shot (causing the heart to stop beating because there is no brain, causing lack of oxygen to the brain in the case of a spine shot). You can also do this with a wounding shot that gets infected leaving the organism to die by other means. Most of our dead in wars leading up to WWI were from infection and sickness, not gunshots.

Even a 470 Nitro Express solid can bounce off the boss of a Cape Buff, as recounted by Capstick. The lesson to be learned is that shot placement matters more than caliber no matter what you happen to be toting.

Attempting to reduce lethality down to so many foot pounds of energy or slugs of momentum within some "kill zone" is a fools errand. And it is also just a way for people to start arguing which caliber is better using bad psuedo-science in an attempt to add the veneer of credibility to there personal preference. See any "9mm vs. 45" argument for an example of this.

Jimro
 
tdoyka said:
Nothings works each and every time.
Click to expand...

I've found that these three things together always work 100% of the time.

1. Proper shot placement
2. Adequate bullet construction
3. Enough impact velocity to ensure penetration into the vital organs with proper bullet expansion.

If you have these three things on your side you'll have a dead animal every time. Maybe not a DRT, but dead in short order with minimal tracking. Using most hunting bullets if you have an impact velocity of at least 1800 fps you'll have adequate expansion and penetration to get the job done. One thing I have found to.create a bigger reaction on impact is a faster twist barrel, I'm of the belief that the faster a bullet spins the more violently it expands on impact. However a faster twist barrel doesn't kill any better than dead.
 
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