Energy Dump - A Self-Defining Term

2500 shootings in 2001 in ONE city? My friend, you need to move, because Bagdad is apparently safer.

Wait a minute? Argentina? 3rd world skinny people? I've got a box of RCBD wonder rounds guaranteed to make your assailant unborn. My friend the Super Cop shot 300 people with it and they all exploded. I'll sell it for what I paid if you're interested.

^Some quick googling:

According to government statistics, over 1,300 people were murdered last year in the Buenos Aires suburbs,

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(2001)

I might believe there are 2500 shootings after seeing that. It has approximately double the population of Philadelphia, and aren't they on track to have 500-600 murders this year? Seems plausible to me.

2500 shootings in 2001 in ONE city?

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So said the chief of police, the source is there for you to translate if you wish.

FerFAL

If you have a hollow point bullet that travels just as far as the FMJ bullet, but expands (thereby making a bigger hole), why wouldn't you want that? Or should we all just forget it and shoot FMJ only. Of course, it would be cheaper, now wouldn't it....

If you have a hollow point bullet that travels just as far as the FMJ bullet, but expands (thereby making a bigger hole), why wouldn't you want that?

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Then you would have a bullet that makes a wide, deep hole -- and as long as you can put it in the right place, who could ask for more?

Then you would have a bullet that makes a wide, deep hole -- and as long as you can put it in the right place, who could ask for more?

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Magic...er, I mean hydrostatic shock

I know wounds outside the path of the bullet can happen, I just don't think they happen with any kind of consistency when talking about handguns. I realize a higher energy round may inflict more pain, but if I'm shooting it's to kill and kill right there, so if it takes all 16, or 32, or 48 so be it.

Maybe it's just the way I was taught being raised in Indiana; fight force with overwhelming counterforce (ie barrage of bullets). In my mind, no matter what I'm shooting, be it 9mm/.45 or 10mm+P/.44mag, Im going to be shooting as fast as I can until the target drops and stops moving.

While a .44mag MAY drop them with the first shot due to cavitation or hydrostatic shock, if it doesn't you try again right? With the 9mm/.45, you'd already have 2-3 rounds on target and squeezing on the 4th. That's more chances at a CNS hit and more total energy 'dumped' into the target. I don't know if 2-3 bullets in very rapid succession at 400FPE each has as much 'hydrostatic wounding potential' as a single .44mag at 900FPE, maybe Dr. C can elaborate on the De/Dx equation. Is Dx supposed to be difference in time (Dt)?

Also, I don't know a single human being who carries a .44mag or a 10mm for defense. Do you? I don't know of any PDs that even have those as optional for officers (though I'm sure there are many spread out). In fact, I'm pretty sure both of these rounds were developed specifically to enhance penetration over what was previously available, not to liquify innards.

I understand what you High Energy folks are saying. I do believe the wounding mechanisms you discuss exist, even in handgun rounds to some extent, and I certainly don't discount the potential psychological effect higher energy rounds may be able to deliver. I just don't think it's a particularly great idea to base one's self defense ammunition on energy values and anecdotes moreso than bullet design and the obvious fact that two holes are better than one.

A wise man once said, "Anyone worth shooting once is worth shooting twice."

A wiser man said, "Shoot as long as the target is there."

I don't know a single human being who carries a .44mag or a 10mm for defense. Do you?

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they're several who frequent this sight and me, although I don't often.

squeezing on the 4th

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practice your mozambique sp? drill, 2 to the body 1 to the head.surely all this time we spend debating something ny half of us belive.we have practiced shooting enough to make a head shot.
or do we not all agree head shots work.

<sigh>

Just like always. Some facts, a lot of opinions, some insults, a lot of squabbling. Gosh, it reminds me of a family reunion!



All I know about the matter at hand is what I think I know, if that makes sense. And what I think I know is more of a series of questions than anything else. Here's what:

Bullet A has 500 ft-lbs of energy, strikes the target, and penetrates to exactly 12 inches, or one foot.

Bullet B has 1000 ft-lbs of energy, strikes the target, and also penetrates to exactly one foot/12 inches.

Isn't Bullet B going to be more destructive because of the resulting force (energy divided by penetration depth)? Of course, I understand that some of that force may go into deforming the bullet and creating heat from friction, but at least some of it must go into doing damage to the target. It just seems commonsense to me. There's got to be more to it than just the hole and the penetration depth.

So is this not what is suggested by the idea of Energy Dump?

Bullet A has 500 ft-lbs of energy, strikes the target, and penetrates to exactly 12 inches, or one foot.

Bullet B has 1000 ft-lbs of energy, strikes the target, and also penetrates to exactly one foot/12 inches.

Isn't Bullet B going to be more destructive because of the resulting force (energy divided by penetration depth)? Of course, I understand that some of that force may go into deforming the bullet and creating heat from friction, but at least some of it must go into doing damage to the target. It just seems commonsense to me. There's got to be more to it than just the hole and the penetration depth.

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Why must it go into doing damage? What if it just temporarily displaces the tissue even further but still nowhere near enough to stretch its past its limit of elasticity?

mavracer said:

because if the BG is 6' 150 lbs. 6" is an exit wound.and I'm not saying mag-safe or glaser are good for SD for that same reason.I was in agreement that under most circumstances its not sufficient.

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You didn't really address what I asked you, 6" of penetration in gelatin is not 6" of penetration in a shoot. I posted the autopsy study from Dr Wolberg who checked the penetration depth of 28 gun shot wounds by the SJPD. The average penetration depth was 13.2" inches. I'm a big guy, 6'3" and about a size 50 chest. Front to back it looks like I'm about 8" at the chest. Obviously all 28 shots didn't go into people 50% bigger than me. So whats going on that makes you think a 6" gelatin round would go through a skinny guy?

On the surface it sounds great to think that a guy who has a chest 6" deep is going to be penetrated completely by a round that does 6" in gelatin. I think this is one of the important lessons from this thread though, the gelatin is just a benchmark for testing. In real life shootings it looks like the bullet needs to penetrate far more tissue than you might imagine it would. To me this is just another example of where "common sense" fails to actually hold up and little bit of science teaches us an important lesson.

I went through five pages to see if I bothered commenting on this never ending arguement. I really don't know why I should care about the subject except in pure theory. Facts are facts and a well placed .380 will kill a man, let alone the 9 or .357.

http://www.thehighroad.org/showthread.php?t=292871&highlight=Courtney

"common sense" would be not to argue with someone who agrees with you.But if you insist ,A:you are taking my comment way to serious.
B:assuming my skinny guy is 6" front to rear 3-4" with a highly frangible round is going to maserate (sp?) the heart/lungs.
C: my 50" chest is just under 12" deep, which doesn't matter.
D:I don't think this has anything to do with stopping skinny BGs

I posted the autopsy study from Dr Wolberg who checked the penetration depth of 28 gun shot wounds by the SJPD. The average penetration depth was 13.2" inches. I'm a big guy, 6'3" and about a size 50 chest. Front to back it looks like I'm about 8" at the chest. Obviously all 28 shots didn't go into people 50% bigger than me.

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if you think your only 8" and average depth is 13.2" it sounds like you are questioning your own arguement.

Why must it go into doing damage?

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I don't know. Maybe because it would make fools out of those who believe in Energy Dump?

Well, I guess this leads to a whole series of other questions. Like just how much force can tissue withstand before it tears or gets damaged? Is it dependent on tensile strength? (My guess is yes, but that's only a guess.)
But I do know that if something stretches, then it can also get damaged or weakened. Even basic physics books got into such things as deformation, etc. I know I can pull on the elastic in my whitey-tighties with such force that they'll fall down to my ankles when I try to put them on. (I'm not being completely facetious here, really.) What I'm saying is I don't see how that sudden, violent stretching of tissue such as results from a gunshot wound can avoid doing damage.

Quote:
Bullet A has 500 ft-lbs of energy, strikes the target, and penetrates to exactly 12 inches, or one foot.

Bullet B has 1000 ft-lbs of energy, strikes the target, and also penetrates to exactly one foot/12 inches.

Isn't Bullet B going to be more destructive because of the resulting force (energy divided by penetration depth)? Of course, I understand that some of that force may go into deforming the bullet and creating heat from friction, but at least some of it must go into doing damage to the target. It just seems commonsense to me. There's got to be more to it than just the hole and the penetration depth.

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Why must it go into doing damage? What if it just temporarily displaces the tissue even further but still nowhere near enough to stretch its past its limit of elasticity?

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The retarding force between the bullet and tissue causes more than tissue stretch. Tissue stretch is caused by tensile stresses induced by the retarding force. There are compressive and shear stresses also. It is the shear stresses that create the prompt damage: a region of damaged tissue close to the bullet path but not directly crushed by the tissue. Compressive stresses can also damage tissue.

In addition, at 1000 ft-lbs transferred in 12", you've got enough of a temporary cavity to reliably damage liver, spleen, kidneys, and neural tissue, and to begin to damage lung and vascular tissue, especially if the bullet fragments at all (fragmentation and temporary stretch work together to create greater wounding than stretch alone.) Even at 500 ft-lbs transferred over 12", temporary stretch can cause significant wounding to lungs and vascular tissue if the bullet fragments significantly.

Michael Courtney

Why must it go into doing damage? What if it just temporarily displaces the tissue even further but still nowhere near enough to stretch its past its limit of elasticity?

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It will do that, too. But in the process of the energy being distributed, there will be additional areas that sustain damage. Perhaps if the extra energy was being released in a nice, slow manner, but if it's to be transferred over the same area, there will be additional elastic and plastic deformation.

It is the shear stresses that create the prompt damage: a region of damaged tissue close to the bullet path but not directly crushed by the tissue. Compressive stresses can also damage tissue.

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Hmm, that explains the lung damage I've seen in deer I've shot with the .357 magnum. With impact energies of just about 600-700 ft lbs, well under 1000, I observed a 3" diameter path of tissue destruction in lung tissue surrounding the actual path of the bullet. I've been told I was FOS by the crush cavity guys, but I saw what I saw. BTW, I was using a 158 grain hard cast SWC and there was NO bullet expansion, exit wound about the size of the entry wound and complete penetration. The bullet does have a very flat, wide profile, though, cast from a Lee gas check mold.

Some of these Facklerites need to go hunting.

How many deer have you shot with a handgun that you observed this effect in? A percentage would suffice.

How many times when shooting a deer from hiding do you have to make quick followup shots?

How many times was the deer holding a loaded weapon to shoot back with?

How many times were you surrounded by multiple deer with bad intentions?

Lung damage? Whoopty do, we've already determined that an attacker can last as long as 20 seconds with NO HEART. Lung damage or not, if your target has a gun he's going to be shooting back if he's not dead.

Until someone can show me a bullet design that actually harnesses that extra energy against internal tissue consistently, all I can count on are the holes I'm making, anything else is just a bonus. Those 'maybe bonuses' don't seem to be worth going from 16 rounds to 6, or adding an extra 1/4 second between shots. To each his own.

The retarding force between the bullet and tissue causes more than tissue stretch. Tissue stretch is caused by tensile stresses induced by the retarding force. There are compressive and shear stresses also. It is the shear stresses that create the prompt damage: a region of damaged tissue close to the bullet path but not directly crushed by the tissue. Compressive stresses can also damage tissue.

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That's interesting. Thank you, Dr. Courtney.
Food for thought.

Hmm, that explains the lung damage I've seen in deer I've shot with the .357 magnum. With impact energies of just about 600-700 ft lbs, well under 1000,

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I mainly just pulled the 1000 figure out of the air for ease of comparison, but I did have the .223/5.56 at the back of my mind. The 500 figure might be a 10mm, but that one I purely pulled out of the air.

So, "dump" or not, it's almost commonsense that energy does play a role in wounding.

Until someone can show me a bullet design that actually harnesses that extra energy against internal tissue consistently, all I can count on are the holes I'm making,

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That extra energy is harnessed to make a bigger hole through bullet design, such as in JHPs. That's the best way to use the energy, and that's all there is to it. Better choice of bullet design will affect wounding more than 20 or 30 extra ft-lbs of energy.

Many elastic materials have a strain-rate dependence also, such that if stretched/deformed too quickly, it will suffer a severe loss in energy absorption prior to fracture. I don't know if human tissue is subject to this, but speed of deformation may also have an effect.

How many deer have you shot with a handgun that you observed this effect in? A percentage would suffice.

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Two at about 30 and 50 yards. One with a carbine at about 80.

How many times when shooting a deer from hiding do you have to make quick followup shots?

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None and none went more'n 25 yards from where shot. But, quick follow ups with my SP101 aren't that hard to do in a self defense scenario. I've out shot a lot of cocky shooters with 1911s while shooting a revolver. It ain't the gun, it's the man behind it. The one thing those deer had in common was well placed shots, all lung shots.

How many times was the deer holding a loaded weapon to shoot back with?

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I'm talking about wound ballistic theory here, but I'll shoot til the threat stops.

How many times were you surrounded by multiple deer with bad intentions?

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Irrelevant to the discussion.

Lung damage? Whoopty do, we've already determined that an attacker can last as long as 20 seconds with NO HEART. Lung damage or not, if your target has a gun he's going to be shooting back if he's not dead.

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So, what you're telling me is that your .45 ACP can do better than my .357 magnum at stopping a fight? I don't think so. Don't be delusional. Handgun calibers on the upper end of the defense spectrum are still handguns. I've seen a guy walk into the door of an emergency room holding in his guts, shot point blank with a 12 gauge. He drove himself to the ER. I make no claims that the .357 Magnum WILL ALWAYS KILL fast and effectively in one shot. I simply am discussing terminal ballistics, not gun fights. That's a bit off topic.

The problem with such discussions is that the facklerites are supporting the .45ACP above all else as the ONLY handgun cartridge of worth and all other platforms than the 1911 or the .45ACP cartridge should not exist. It's not so much about terminal ballistics theory as supporting big and slow and the 1911 platform. Wrap yourself in a 100 year old flag and get on your knees when you see a picture of Jeff Cooper. Well, I'll take an SP101 loaded with 140 grain full power JHPs making 550 ft lbs at the muzzle over any 1911 for personal carry, thank you very much. It's compact, it's powerful, it's easy to carry, and it's safe to carry. It also goes bang every time, no stove pipes, no tap rack bang. No need to carry only FMJ. Hollow points work fine in it. It's my choice. I've been there, done that with 1911s. That's my choice until the 1911 folks succeed in legislation to end production of revolvers. Well, it's not my ONLY choice. In fact, I do have an occasionally carry a P90 Ruger in .45 and like the 9mm in pocket autos, but the .357 revolver is my first center fire handgun, a Security Six, and still my favorite platform and caliber.

How many deer have you shot with a handgun that you observed this effect in? A percentage would suffice.

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from his story I'll answer 1deer 100% so it CAN happen.

How many times when shooting a deer from hiding do you have to make quick followup shots?

How many times was the deer holding a loaded weapon to shoot back with?

How many times were you surrounded by multiple deer with bad intentions?

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I thought we were talking about energy transfer and wounds not tactics so I fail to see the relavance of armed deer.

Lung damage? Whoopty do, we've already determined that an attacker can last as long as 20 seconds with NO HEART. Lung damage or not, if your target has a gun he's going to be shooting back if he's not dead.

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this is where it makes a difference that we are not shooting deer you see a man may/may not get hit in the lung and decide to drop the gun, the more damage done the more likely this may happen.

Until someone can show me a bullet design that actually harnesses that extra energy against internal tissue consistently, all I can count on are the holes I'm making, anything else is just a bonus. Those 'maybe bonuses' don't seem to be worth going from 16 rounds to 6, or adding an extra 1/4 second between shots. To each his own.

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you use a 32 acp. with fmj then?cause they make holes and you can shoot real fast and accurate.me, I use them new fangled hollow points that dump more energy into the target by expanding aginst the resistance of the BG body,therefore doing more damage directly and indirectly.BTW my splits on double taps with my delta elite are only 1/4 second they only drop about .05 seconds with my 9mm.

That extra energy is harnessed to make a bigger hole through bullet design, such as in JHPs. That's the best way to use the energy, and that's all there is to it. Better choice of bullet design will affect wounding more than 20 or 30 extra ft-lbs of energy.

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Okay, so if my 147gr. Subsonic Rangers average 14" penetration and .68" recovered diameter, what advantage would I get from a +P 147gr bullet?

I might get some more 'pressure wave' effect (whatever that might entail).
I might get a bit more expansion, but then I might get less. Yes that's right, some bullets expand less at high velocity than lower velocities. Velocity is no where near as important as bullet design when it comes to expansion.

If I'm shooting hard cast lead, and i want to make that deform, then hell yes I need some good velocity. When using softer lead with a thin but hard jacket, pushing the bullet too fast can actually fragment the bullet in mid air.

this is where it makes a difference that we are not shooting deer you see a man may/may not get hit in the lung and decide to drop the gun the more damage done the more likely this may happen.

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Beyond that, a man is not standing broadside where you can penetrate both lungs with one shot. Best shot is center mass near the sternum, put the bullet close to the spine and THEN perhaps that pressure wave will be more than theoretical. I've seen deer lung shot (one this season) drop like a sack of taters when the bullet hit near, but not on the spine and only lungs were hit. I ain't sayin' that'll happen every time, I'm just sayin' on a human, I ain't shootin' behind the shoulder to save meat damage, I'm shootin' center mass. And, yes, given the choice, I'll always seek more bullet energy in the caliber. If I could get a controllable SP101 firing .41 or .44 magnum, that'd be better. But, in a small frame revolver, .357 is about it for controllable horsepower.

What I was explaining was lung damage away from the path of the bullet anyway, the apparent effects of the pressure wave as Dr. Courtney describes. I wasn't talking about a gun fight or tactics in a gun fight.

Okay, so if my 147gr. Subsonic Rangers average 14" penetration and .68" recovered diameter, what advantage would I get from a +P 147gr bullet?

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You would most likely get additional tissue damage either by increased size, or through increased depth. If you're happy with your regular, there's no need to go +P - your choice. But that is what would happen for the mechanics of it. Assuming the expansion functions properly, the +P WILL do some finite amount of additional damage.

Velocity is no where near as important as bullet design when it comes to expansion.

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Pretty much what everyone has been saying.