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thegriz18
11-01-2010, 00:14
I've noticed that everyone makes a big deal about pistol bullet penetration depth listing 12 inches as the bare minimum a bullet must penetrate to be considered reliable for use. However, the .223 is used by many of these same agencies and the rounds that are used in .223 ammo typically barely make 12 inches in gel. Am I missing something, or does that not make any sense at all?

glock20c10mm
11-01-2010, 00:58
No, you're not missing anything. The 12" number is nothing more than a good rule of thumb. Even Dr. Fackler said that the ~8" penetration depth that some of the 9mm 115gr HP loads muster up is usually enough.

Me personally, as long as a given load is good for around 10" penetration depth in clothed gel, I'm happy. And when I'm not in bear country, that's why I like Double Tap's 10mm 135gr Nosler bullet load. For most situations I'm not interested in more than 11" penetration depth.

Sometimes in my spare mag I'll carry a heavier bullet weight just in case it's needed (of course that will only help if I have time to switch mags :shocked: ).

12" penetration depth is not a requirement. Some guys want their carry load to penetrate more than that, and others like me, less.


Good Shooting,
Craig

DocKWL
11-01-2010, 03:31
I've noticed that everyone makes a big deal about pistol bullet penetration depth listing 12 inches as the bare minimum a bullet must penetrate to be considered reliable for use. However, the .223 is used by many of these same agencies and the rounds that are used in .223 ammo typically barely make 12 inches in gel. Am I missing something, or does that not make any sense at all?

What you are missing is the character of the work done by a rifle bullet as compared to a hangun bullet. Two totally different animals.

English
11-01-2010, 05:27
I've noticed that everyone makes a big deal about pistol bullet penetration depth listing 12 inches as the bare minimum a bullet must penetrate to be considered reliable for use. However, the .223 is used by many of these same agencies and the rounds that are used in .223 ammo typically barely make 12 inches in gel. Am I missing something, or does that not make any sense at all?

The 12" minimum penetration requirement comes from the FBI and is combined with a 16" or 18" (I don't remember which) maximum. Following the Miami shootout in which bad guys continued to kill good guys after receiving shots which would have killed them sooner if they had penetrated just a little further, the FBI decided that they needed a better round than the .38 Sp and set out to find one. Penetration depth was part of the testing criteria. The FBI were also very concerned with fights with BGs in or behind cars and so they wanted enough penetration to do a lot of damage after a bullet had passed through a car body or windscreen.

If you look at the various photographs of bullet damage to ballistic gellatine which are infiltrated with die, you will see that the last third to a quarter of the penetration is actually smaller than caliber. In contrast the earlier part, even from the 147gn 9mm, which is the worst, is very significantly greater than caliber. In this region the damage done by the bullet is done to a large volume of gel or tissue and so the heart, for example does not need to be hit directly by the bullet to be incapacitated. In the later section of its travel, the only damage is to tissue on the direct path of the bullet and so this region is almost wasted relative to a rapid incapacitation except for very fortunate shots. This does not mean entirely wasted of course, as the autopsies from that event showed, but bullets tend to deflect once they hit a body and so even the most well placed shots can miss their internal target.

The reality of gunfights is that BGs do not stand upright and square on while you shoot at them and so a bullet might hit an arm before it gets to the body or the shot might pass at some odd angle through a depth of body before it gets to something vital. So there is considerable justification for the FBI's depth of penetration criterion which we can think of as a major damage for the first 8 inches and minor damage thereafter. Often enough, minor damage is better than none.

What you then have to consider is the applicability of the FBI model to a civilian gunfight. Do you expect to be fighting BGs behind cover or is the more likely scenario a fight at close range with no cover. If it is the latter then penetration becomes less significant and a wide zone of damage becomes more significant. there is no perfect answer to all scenarios.

English

481
11-01-2010, 08:53
What you are missing is the character of the work done by a rifle bullet as compared to a hangun bullet. Two totally different animals.

Doc,

As I've come to expect, you are spot on. :supergrin:


For those with open minds interested in learning more about the characteristics of either phenomena (handgun and rifle projectile penetration and terminal behavior) there are excellent sources available that can provide scientifically sound material explaining the nature of the two.

A valid perspective and understanding of handgun bullet penetration mechanics can be obtained by reading, "Bullet Penetration", by Duncan MacPherson. While heavily reliant upon math/calculus to illustrate the operation of his well researched model, a cursory reading "around the math" involved can provide an improved understanding of terminal ballistics to the lay reader.

Written and published more than a decade prior (1990) to MacPherson's work is that of Professor Carroll E. Peters (Professor of Mechanical and Aerospace Engineering, University of Tennessee), which also succeeds in describing valid mathematical models for the penetration of both rifle and pistol bullets.

Finally, there is the work of Mssr. Jean Victor Poncelet (1788-1867), a French mathematician and engineer who served under Napoleon during the War of 1812, who developed a differential equation (employing hybrid methodology) for expressing mathematically the penetration of (non-deforming) bullets of his day. While it does not address today's expanding designs (like JSPs, JHPs and EFMJs), it does provide an illuminating insight into the basics of the discipline of Penetration Mechanics.

I'd encourage anyone truly interested in learning more about bullet penetration and terminal performance to have a look at these three predictive models.


:)

fredj338
11-01-2010, 09:23
All good points. Once bullets get above 2000fps impact vel, they act diff when striking flesh. So a shallower depth may happen w/ certain 223 loads but the wound will be far greater in volumn. For handguns, as noted, you may have to shoot through add'l. body parts to get to vitals. A really big guy can have a forarm that is 6"-7" in dia. THat is taking quite a bit of steam off your bullets ability to get to the good stuff.

BOGE
11-01-2010, 09:24
...Following the Miami shootout in which bad guys continued to kill good guys after receiving shots which would have killed them sooner if they had penetrated just a little further...


Incorrect. How many times does this BS have to be quashed. :upeyes: The wound in question was mortal. It wouldn`t have mattered it was a .50 BMG as the perp in question was RESOLUTE and wanted to kill and adrenaline is an an amazing drug.

It doesn`t matter if the bullet penetrates fully as the purpose of a gunshot wound is exsanguination (bleeding out), barring a CNS hit. You are diverting blood from its intended purpose. Nothing more, nothing less. If a person is bleeding into their own abdominal cavity from a gunshot wound it makes no difference if their are two holes or one. THE BLOOD IS NOT REACHING ITS INTENDED SOURCE, thereby shutting down the body (shock). Think about it.

uz2bUSMC
11-01-2010, 12:03
All good points. Once bullets get above 2000fps impact vel, they act diff when striking flesh. So a shallower depth may happen w/ certain 2234 loads but the wound will be far greater in volumn. For handguns, as noted, you may have to shoot through add'l. body parts to get to vitals. A really big guy can have a forarm that is 6"-7" in dia. THat is taking quite a bit of steam off your bullets ability to get to the good stuff.

How do they act different while at or above 2000fps?

uz2bUSMC
11-01-2010, 12:07
What you are missing is the character of the work done by a rifle bullet as compared to a hangun bullet. Two totally different animals.

Can you describe the difference in the character of work between the two? You've had Duncan's book for quite a few years now, have you managd to finally get through it? I know it took a couple of those years just to get half way. I'm listening...

G31
11-01-2010, 12:13
481, I have never read the works you have cited, but have to ask a question. Do these works address bullet penetration, actual observed wound ballistics, or both?

One problem I've seen with a strict math/science analysis is it puts too much emphasis on some of the smaller, less observable aspects of physics and what "should happen", rather than the actual observed (medically) reaction. For example, the idea that added energy transfer makes a difference in effectiveness between two different pistol rounds is valid in physics, but is unseen in the real world against humans. Same goes for almost all of the other theoretical influences brought by math/physics.

Basically, I do not question the mathematical penetration information, as you can't outright defy physics, but would highly question the idea that any of the other info (if presented) translates to defensive/offensive use without any verified observation in the real world.

Do these resources make conclusions to the effectiveness of bullets strictly using numbers?

English
11-01-2010, 12:23
Incorrect. How many times does this BS have to be quashed. :upeyes: The wound in question was mortal. It wouldn`t have mattered it was a .50 BMG as the perp in question was RESOLUTE and wanted to kill and adrenaline is an an amazing drug.

It doesn`t matter if the bullet penetrates fully as the purpose of a gunshot wound is exsanguination (bleeding out), barring a CNS hit. You are diverting blood from its intended purpose. Nothing more, nothing less. If a person is bleeding into their own abdominal cavity from a gunshot wound it makes no difference if their are two holes or one. THE BLOOD IS NOT REACHING ITS INTENDED SOURCE, thereby shutting down the body (shock). Think about it.

I do accept that my memory might be at fault and I have not read the report recently, but my memory was that a critical shot on one of the BGs stopped an inch short of the heart. This would have been a mortal wound but if it had penetrated the heart the BG would have been incapacitated within 15 to 30 seconds. As it was his relatively slow rate of exsanguination allowed him to get out of the car and work his way round behind what I think were two FBI agents who he killed. If the bullet had pentrated that extra two inches he could not have done this.

English

BOGE
11-01-2010, 13:09
I do accept that my memory might be at fault and I have not read the report recently, but my memory was that a critical shot on one of the BGs stopped an inch short of the heart. This would have been a mortal wound but if it had penetrated the heart the BG would have been incapacitated within 15 to 30 seconds. As it was his relatively slow rate of exsanguination allowed him to get out of the car and work his way round behind what I think were two FBI agents who he killed. If the bullet had pentrated that extra two inches he could not have done this.

English

English, write this down and remember it. The ME stated ON THE RECORD that the wound was mortal and the victim would not have survived had the wound ocurred in the best trauma center in the world. Some people just don`t want to die when we want them to.

fredj338
11-01-2010, 13:17
Incorrect. How many times does this BS have to be quashed. :upeyes: The wound in question was mortal. It wouldn`t have mattered it was a .50 BMG as the perp in question was RESOLUTE and wanted to kill and adrenaline is an an amazing drug.
Think about it.
I think the word is "eventually" fatal. Yes, Platt would have bled out, eventually. If the bullet went another 2", he would have bled out faster. It's not compeletly arbitrary; put a ruler across your chest from your shoulder, it's just about 12" to get penetration through the heart. At 10", my heart is still intact & I am in the fight longer, at 12" my heart has a very large hole in it & I am bleeding out sooner than later. One does not need to be a medical examiner to know that a big hole in your heart is better than just a hole in your chest cavity.
How do they act different while at or above 2000fps?
Impact vel above 2000fps or so start to tear flesh through cavitation. There have been studies done by professional hunter in Africa on large game & when vel starts to matter w/ big bore rifles, most claim some place around 2000fps based on post mortem of the animal's tissue after the shot. Again, always assuming the bullet holds together to do damage & does not frag & lose penetration.

481
11-01-2010, 13:41
481, I have never read the works you have cited, but have to ask a question. Do these works address bullet penetration, actual observed wound ballistics, or both?

G31,

To varying degrees each of these works addresses both aspects.

One problem I've seen with a strict math/science analysis is it puts too much emphasis on some of the smaller, less observable aspects of physics and what "should happen", rather than the actual observed (medically) reaction. For example, the idea that added energy transfer makes a difference in effectiveness between two different pistol rounds is valid in physics, but is unseen in the real world against humans. Same goes for almost all of the other theoretical influences brought by math/physics.

None of the three works cited above deviate into the needless pursuit of minutae from their objectives. All remain firmly focused upon the long proven disciplines of calculus, physics and (relatively simple) fluid dynamics.

Basically, I do not question the mathematical penetration information, as you can't outright defy physics, but would highly question the idea that any of the other info (if presented) translates to defensive/offensive use without any verified observation in the real world.

We can only measure that which can be measured. Intangibles are just that- intangible. Any attempt to quantify/qualify them is ill-advised and likely to make one a candidate for the Giggling Academy, if they are not one already.

Do these resources make conclusions to the effectiveness of bullets strictly using numbers?

Nope.

There is no way to quantify the phenomena that some refer to as "Stopping Power" (what units does "stopping power" or any other proposed construct claiming to define "terminal effectiveness" have?) in any meaningful, mathematical sense of the concept. Those who insist that there is are only displaying their resolute unwillingness to understand that there are far, far too many variables (which I will not even attempt to list here for my time's sake) involved in achieving the incapacitation of an assailant to do so.

These works remain within the bounds of the disciplines and research mentioned above. No wild, speculative theorizing. Just quantitative modeling.

Look 'em up. They are well worth the read!

:)

thegriz18
11-01-2010, 15:00
The point I am making is this.

Vital organs don't change in distance between a rifle shot and handgun shot.
Most .223 rounds penetrate 8-9 inches in bare gel, fragment with or without a barrier and we call them satisfactory rounds. Then we tell people that if a handgun bullet doesn't penetrate 12 inches it won't hit vitals, or at least not at a reliable rate. A .223 bullet will encounter the same barriers as handgun bullets, yet these bullets tend to fragment, we call them satisfactory and then moan about core/jacket separation in handgun bullets. I'm not saying the .223 is anemic, all I'm saying is calling 12 inches the minimum for a handgun and 7-8 inches the minimum for a rifle is stupid. We tend to discard handgun rounds that don't make 12 inches as failures, yet .223 rounds that make 8 inches pass. Can anyone else see how that makes zero sense?

I'm simply questioning why there are two standards for each. Granted a rifle bullet will produce different damage than a handgun bullet, but shouldn't it be held to higher standards (or at least the same) than a handgun bullet?

Perhaps we are wasting too much time with handgun bullets penetrating 12 inches when we should be spending time getting them to act like .223 rounds. Or maybe we should be making .223 bullets that don't fragment and stay together (Barnes TSX?). Which is it? Who is following my logic?

English
11-01-2010, 15:06
English, write this down and remember it. The ME stated ON THE RECORD that the wound was mortal and the victim would not have survived had the wound ocurred in the best trauma center in the world. Some people just don`t want to die when we want them to.

I am glad for the confirmation that my memory was not at fault. The question is entirely one of time if we assume determination to keep fighting. With ones heart shot out, blood delivery to the brain ceases immediately but there is still enough blood in the brain and muscles to keep fighting effectively for 15 to 30 seconds according to the FBI. With a smalll hole through one wall of the heart that time might increase a little but most probably the heart will go into fibrillation and will not deliver any significant blood to the brain.. With almost any other gunshot wound which causes eventual death by exsanguination that time jumps to minutes and might be as long as 30 minutes but is still a mortal wound.

What the FBI was looking for in its tests was a round with a greater probability of a faster incapacitation. I would guess that Platt's route from that wound to killing another agent was 4 or 5 minutes. If his heart had been punctured he would not have got there. Determination to keep fighting stops when you loose consciousness.

English

English
11-01-2010, 15:09
griz,
You mustn't say things like that. Some people will be very offended.

English

uz2bUSMC
11-01-2010, 15:33
Impact vel above 2000fps or so start to tear flesh through cavitation. There have been studies done by professional hunter in Africa on large game & when vel starts to matter w/ big bore rifles, most claim some place around 2000fps based on post mortem of the animal's tissue after the shot. Again, always assuming the bullet holds together to do damage & does not frag & lose penetration.

I'm assuming that you are talking temporay cavitation. I'm gonna call cherry pick on this one Fred. Not because that's what you do, on the contrary, I've read enough of your post over the years to know that is not the case but because that sounds like the case here.

2000 might be a good starting point for hardcast bullets which sounds about right for the an african study. I'm sure, because of a hardcast bullets profile, you will have to drive it fast to do damage via temp cavitation, however... this is not gonna hold true as a general rule of thumb. The rate of transfer is what will affect cavitation the most, i.e. a handgun bullet traveling @1700fps and penetrating only 10" may have greater temp cav than a hardcast rifle bullet traveling 2200fps which penetrates some 40" (because it doesn't deform). It's is all dependant upon the interaction of the projectile and the retarding forces, this interaction changes largely on rate of tranfer.

You have a link to the study, or at least more info???

uz2bUSMC
11-01-2010, 15:42
The point I am making is this.

Vital organs don't change in distance between a rifle shot and handgun shot.
Most .223 rounds penetrate 8-9 inches in bare gel, fragment with or without a barrier and we call them satisfactory rounds. Then we tell people that if a handgun bullet doesn't penetrate 12 inches it won't hit vitals, or at least not at a reliable rate. A .223 bullet will encounter the same barriers as handgun bullets, yet these bullets tend to fragment, we call them satisfactory and then moan about core/jacket separation in handgun bullets. I'm not saying the .223 is anemic, all I'm saying is calling 12 inches the minimum for a handgun and 7-8 inches the minimum for a rifle is stupid. We tend to discard handgun rounds that don't make 12 inches as failures, yet .223 rounds that make 8 inches pass. Can anyone else see how that makes zero sense?

I'm simply questioning why there are two standards for each. Granted a rifle bullet will produce different damage than a handgun bullet, but shouldn't it be held to higher standards (or at least the same) than a handgun bullet?

Perhaps we are wasting too much time with handgun bullets penetrating 12 inches when we should be spending time getting them to act like .223 rounds. Or maybe we should be making .223 bullets that don't fragment and stay together (Barnes TSX?). Which is it? Who is following my logic?

Griz,

I'll tell it to you like this...

People here have a hard time crossing thresholds. They like it to be "a rifle is a rifle and a handgun is a handgun". They can't keep simple things in perspective. An example... a while back I had suggested that a 10mm from a 6" bbl was roughly the same as 5.56 from a short BBL (which it is), and this caused a bit of a stink. The reason? 'Cause people don't want to accept that a pistol can do the work of a rifle. What you're asking is a taboo query... these people will discuss penetration depth adnauseum for pistols but breeze right by the subject with rifles because it is an uncomfortable posibility. You will see most "9 is fine" types in this kind of discussion.

G31
11-01-2010, 17:02
I leave rifles alone, in general, because I don't know their ins-n-outs nearly as much as a handgun wound, so I tend to stay away from rifle ballistics when they get too in-depth. I do know a rifle bullet travelling at handgun speeds will act as a handgun round does, for the most part, but not due to observation, like I do a pistol wound.

I do know there is a point where a round is powerful enough due to velocity to take advantage of energy dissipation, etc., but don't know the magic numbers associated with it.

Under normal handgun velocities and energy numbers, I fall into the "9 is fine" group, as that is what medical science has shown to be as effective as any of the other defensive pistol rounds out there. If you had a .223 round going 1200 FPS, I doubt it would perform well at all. On the other hand, if a 9mm was pushed to rifle velocities, it would probably have a much better effect on the target.

I guess I don't differentiate between types of firearms or rounds associated with them as a sweeping rule, so I could never fall into a "rifle is always better" crowd. It depends on wht the round can accomplish out of the gun it comes from.

fredj338
11-01-2010, 17:12
The point I am making is this.

Vital organs don't change in distance between a rifle shot and handgun shot.
Most .223 rounds penetrate 8-9 inches in bare gel, fragment with or without a barrier and we call them satisfactory rounds. Then we tell people that if a handgun bullet doesn't penetrate 12 inches it won't hit vitals, or at least not at a reliable rate. A .223 bullet will encounter the same barriers as handgun bullets, yet these bullets tend to fragment, we call them satisfactory and then moan about core/jacket separation in handgun bullets. I'm not saying the .223 is anemic, all I'm saying is calling 12 inches the minimum for a handgun and 7-8 inches the minimum for a rifle is stupid. We tend to discard handgun rounds that don't make 12 inches as failures, yet .223 rounds that make 8 inches pass. Can anyone else see how that makes zero sense?

I'm simply questioning why there are two standards for each. Granted a rifle bullet will produce different damage than a handgun bullet, but shouldn't it be held to higher standards (or at least the same) than a handgun bullet?

Perhaps we are wasting too much time with handgun bullets penetrating 12 inches when we should be spending time getting them to act like .223 rounds. Or maybe we should be making .223 bullets that don't fragment and stay together (Barnes TSX?). Which is it? Who is following my logic?
To a point I agree, why I don't hunt deer size game w/ a 223. I believe the newere "heavy" 223 bullets are designed to give greater penetration than the old style 55gr. Also keep in mind, most combatants shot w/ a 223 are hit multiple times, so that's multiple large volumn wounds on a torso or leg or whatever. STill, the high vel rifle bullet does things to flesh no handgun bullet can, especially in FMJ form. While the 12" min for a handgun may seem somewhat arbitrary, again, put a ruler across your chest from point of should to your heart, it's right about 12" for a normal size 5'-10"/190# guy.:dunno:

fredj338
11-01-2010, 17:16
I'm assuming that you are talking temporay cavitation. I'm gonna call cherry pick on this one Fred. Not because that's what you do, on the contrary, I've read enough of your post over the years to know that is not the case but because that sounds like the case here.

2000 might be a good starting point for hardcast bullets which sounds about right for the an african study. I'm sure, because of a hardcast bullets profile, you will have to drive it fast to do damage via temp cavitation, however... this is not gonna hold true as a general rule of thumb. The rate of transfer is what will affect cavitation the most, i.e. a handgun bullet traveling @1700fps and penetrating only 10" may have greater temp cav than a hardcast rifle bullet traveling 2200fps which penetrates some 40" (because it doesn't deform). It's is all dependant upon the interaction of the projectile and the retarding forces, this interaction changes largely on rate of tranfer.

You have a link to the study, or at least more info???
You are correct, & I have always maintaned size of the target matter. You can pepper a 2000# cape buff w/ an entire mag of ammo & he will not likely go down for quite some time unless you get a lucky spine shot. That mass is going to absorb a lot of punishment. My point about the bullet being capable.
With handgun bullet, someplace over 1500fps w/ enough mass to reach vitals from ANY reasonable angle, is certainly going to cause a massive amount of tissue destruction, again, bullet design needs to be taken into account as well as size of the target.
I know you are a 10mm high vel fan & IF you could design a bonded 135gr that has controlled expansion & IF yo ucan drive it safly @ 1500fps+, I think you set up some interesting dynamics. Same for the 357sig & it's bonded bullets going 1500fps+. It still won't be a rifle bullet hitting it's target @ speeds above 2000fps.
Unortunately, the study was in an African mag I used to get regularly. I'll look for it & send you a scan if I find it.:wavey:

uz2bUSMC
11-01-2010, 17:23
You are correct, & I have always maintaned size of the target matter. You can pepper a 2000# cape buff w/ an entire mag of ammo & he will not likely go down for quite some time unless you get a lucky spine shot. That mass is going to absorb a lot of punishment. My point about the bullet being capable.
With handgun bullet, someplace over 1500fps w/ enough mass to reach vitals from ANY reasonable angle, is certainly going to cause a massive amount of tissue destruction, again, bullet design needs to be taken into account as well as size of the target.
I know you are a 10mm high vel fan & IF you could design a bonded 135gr that has controlled expansion & IF yo ucan drive it safly @ 1500fps+, I think you set up some interesting dynamics. Same for the 357sig & it's bonded bullets going 1500fps+. It still won't be a rifle bullet hitting it's target @ speeds above 2000fps.
Unortunately, the study was in an African mag I used to get regularly. I'll look for it & send you a scan if I find it.:wavey:

Cool.

ETA: I've also ran across a study in the past which cape buff were shot with a .338 winny. The said buff dropped in their tracks. The one pullin the trigger admittedly did not want to take the shot with the .338, as he was out for other game, but the opportunity presented itself. Apparently, they cut into the animals head and found hemoraging from damaged vessels... this coorelates to another's study, shhh...

uz2bUSMC
11-01-2010, 17:42
I do know there is a point where a round is powerful enough due to velocity to take advantage of energy dissipation, etc., but don't know the magic numbers associated with it.

-It's not neccessarily due to velocity. Think bullet construction and it's abilty, through construction, to transfer that energy quickly. FMJ is minimal, a pre-frag round is the opposite end of the spectrum - extremely violent transfer.

Under normal handgun velocities and energy numbers, I fall into the "9 is fine" group, as that is what medical science has shown to be as effective as any of the other defensive pistol rounds out there. If you had a .223 round going 1200 FPS, I doubt it would perform well at all. On the other hand, if a 9mm was pushed to rifle velocities, it would probably have a much better effect on the target.

- That's the thing... it's merely diff projectiles pushed to diff velocities with varying constructions. Pistol or rifles- it's irrelevant.

I guess I don't differentiate between types of firearms or rounds associated with them as a sweeping rule, so I could never fall into a "rifle is always better" crowd. It depends on wht the round can accomplish out of the gun it comes from.

.....

G31
11-01-2010, 18:41
Sounds like we agree there. Cool. :)

BOGE
11-01-2010, 23:19
I think the word is "eventually" fatal. Yes, Platt would have bled out, eventually. If the bullet went another 2", he would have bled out faster. It's not compeletly arbitrary; put a ruler across your chest from your shoulder, it's just about 12" to get penetration through the heart. At 10", my heart is still intact & I am in the fight longer, at 12" my heart has a very large hole in it & I am bleeding out sooner than later. One does not need to be a medical examiner to know that a big hole in your heart is better than just a hole in your chest cavity...


Fred, you`re a swell fella, BUT not only are you not a ME you didn`t see the corpse nor examine it. I think I`ll go with the autopsy report by a trained physician and forget about Monday morning quarterbacking. :)

English
11-02-2010, 09:49
Cool.

ETA: I've also ran across a study in the past which cape buff were shot with a .338 winny. The said buff dropped in their tracks. The one pullin the trigger admittedly did not want to take the shot with the .338, as he was out for other game, but the opportunity presented itself. Apparently, they cut into the animals head and found hemoraging from damaged vessels... this coorelates to another's study, shhh...

I have resisted commenting for some time but an interesting thought has just worked its way through my consciousness.

First and foremost, it is energy that does work and in the case of bullet trauma the work is tissue disruption and acceleration. The critical thing with respect to work done by the kinetic energy of the bullet is where and how quickly that energy is delivered.

I would like to believe that we can all agree on the following but I am sure we won't. Death is a common enough consequence of bullet trauma and is often a desireable outcome but the most important thing is incapacitation. If we are hunting we want the animal not to run too far or be unable to attack us after being shot. It isn't necessary that it dies immediatly because if it is incapacitated we can shoot it again or cut its throat to finnish it off. If we are shooting at a person who is shooting at us we need to incapacitate him as soon as possible to reduce the chance of him being able to shoot us. If he dies as a result, that is often a benfit, but the first priority is stopping him from shooting us.

One shot incapacitation is good but partial incapacitation is a lot better than nothing. If our shot makes it harder for the animal to run away or attack us or more difficult for the BG to shoot us, that gives us more chance of making a second or third shot which will conclude the matter without the animal escaping or making a successful attack on us or the BG succeeding in shooting us.

We achieve this by damaging or destroying volition or by damaging or destroying the capability of the body to respond to the will. From evidence from the days when beheadings were common it seems that it was not uncommon for the severed head to show signs of life for a few seconds by eye blinks and mouth movements. If so, the will was still there but there was no way to transmit that to the remainder of the body. Exsanguination will lead to a progressive damage to mental function as well as muscular function where the will is erroded as cosciousness is lost in stages. It is a common strategy of hunters of dangerous game such as Cape Buffalo to aim for bodily incapacitation by shooting for the shoulder. This is more reliable and more immediate than a heart shot. In a man to man fight, if we could shoot the BG in his shooting wrist and then in his other wrist we would achieve a similar effect though as a strategy it would be a poor choice. The point is that it would have produced immediate incapacitation of the bodily function he needed to continue the fight, but that a shot to the lower spine might well leave him able continue shooting at you even though he was totaly unable to control his legs.

We can see that there are many permutations of possible routes to incapacitation, but they come down to damaging the control function or the activation function. In short, this is damage to the CNS, exsanguination, damage to muscles, or damage to bones. These injuries will produce immediate incapacitation, delayed incapacitation or partial incapacitation. The incapacitative effectiveness of those wounds which do not produce rapid unconsciousness will often be moderated by "mind set" or its lack or intoxication which prevents the shootee from understanding the degree of his injury.

So far I think we should all have been able to agree. Where there is continuing dispute within the learned members of Glock Talk is the issue of damage to the CNS. On one side are those who believe that there is enough evidence that a ballistic pressure wave effect (BPW effect) can do enough damage to the brain to produce rapid incapacitation. At the extreme of the other side are those who think that is nonsense though some admit that it might happen with rifle bullets though not with pistol bullets. Most of us here on GT think of the BPW effect as closely related to the work of the Drs. Michael and Amy Courtney but much work has been done elswhere. In particular a study of the brains of gunshot victims who had not been shot in the head showed characteristic damage to cells in the lower brain. That characteristic damage seems to be the same as that found in the Cape Buffalo refered to in the quote above.

The only way in which an animal or a man can be immediately and completely incapacitated, other than by severing the spinal cord at a high level, is by actual damage to the brain. The brain controls the muscles which maintain stance and movement and only if it is damaged in a way that prevents it maintaining the flow of nerve impulses to those muscles will the animal drop on the spot. A heart shot cannot do this because blood remaining in the brain and muscles maintains function for some 15 seconds or longer. Shots to other vital organs cannot do this because at best all they can do is deprive the brain of blood and that then takes some time to produce unconsciousness or semi consciousness. Those hunters who have shot an animal not in the head and not in the spine but have had the animal collapse as though the strings have been cut has to have prduced enough damage to the brain to achieve this effect.

Most hunters will have experienced somthing a little less dramatic in which the animal takes a few seconds to collapse but in which the blood loss could not account for such a rapid collapse. Sometimes the animal looks rather dazed, staggers around and then drops and in other cases it runs a short distance before collapsing. We all have a good idea what "immediate" means but these instances have to be caused by brain damage which is less than great enough to produce immediate incapacitation. The work of the Cortneys used 5 seconds as a cut off to separate such brain injury effects from blood loss effects and exclude animals that were hit in the heart or CNS by accident.

Although it is not accepted by many here on GT the Courtneys' work did no more than quantify what hunters had been seeing since the advent of the rifle but they did it with pistol bullets at pistol velocities. This work makes it clear that such effects are not limited to rifle bullets but apply also to the more powerful pistol bullets with appropriate bullet structure.

What the Courtneys' work showed beyond any reasonable doubt was a strong correlation between the peak pressure of the ballistic pressure wave created by the bullet and the probability of incapacitation within 5 seconds of a single shot remote from the brain, the spinal column and the heart. It did not hypothesize about the mechanism of incapacitation or take instrumental readings of the BPW levels at different times or places in the body. It restricted itself to showing the above corelation.

What follows is speculation mixed with unassailable fact. Within a liquid filled structure, and thed body is mostly that, pressure as such does little or no damage. What does do damage is a pressure differential or gradient because it squashes cells in one direction and stretches them in at least one of the two orthogonal directions. As cells are flattened they keep the same volume but the cell wall has to stretch to accomodate that volume. (The more any cell varies from sperical, the greater must be its surface area relative to its volume.) For any cell there is a limit after which the the cellular membrane is stretched beyond its limit and the cell ruptures. Equally the distortion of the tissue under such a pressure gradient can separate cell to cell adhesion and the tissue tears to greater or lesser extent.

The peak pressures identified as necessary to produce rapid collapse by the Courtneys' work ranged from about 400psi up to 1300psi but those pressures will reduce rapidly with distance from the source. What we don't know is the minimum pressure gradient necessary to produce the characteristic brain cell damage identified by the Czech study but it would probably be possible to do experiments to determine it. Determining the pressure gradient created at the distance from damaged brain cells to source is not simply a matter of the application of the inverse square law because the body is not a homogenous material of infine size. In any case, this is probably not the means by which a sufficiently damaging pressure gradient is transmitted.

My speculation, not limited to me I am sure, is that the transmission is via large blood vessels. As the ballistic pressure wave passes through the body surrounding the bullet track, it stretches and compresses the tissue and collapses blood vessels as it does so. this acts like a pump which squirts blood throught the blood vessels in a massive pulse. It is some of that high pressure high velocity blood that cause the brain cell damage. More speculation of course!

Now, speculation on speculation! If the above model is correct, the strength of that blood pulse is proportional to the volume of tissue in which the pressure gradient is sufficient to collapse large blood vessels within some restriced time. If this is so then not just the peak pressure but the duration of pressure is significant to the damage to the brain cells. From this I conclude that provided some limit of pressure is achieved and maintained over a distance of the bullet's track, the effect might be as great as where the peak pressure is higher but falls away more rapidly. That is, the significant measure of probability of suffidient brain cell damage might be the integral of pressure by the distance over which that presure exceeds some lower limit.

Just a thought!

English

fredj338
11-02-2010, 09:59
Fred, you`re a swell fella, BUT not only are you not a ME you didn`t see the corpse nor examine it. I think I`ll go with the autopsy report by a trained physician and forget about Monday morning quarterbacking. :)

I am not disagreeing w/ the ME, just the staatement it was a fatal or mortal wound. That means little when the guy is still on his feet killing you. Like all the knobs out there that say this or that round has killed more people, blah, blah, blah. It's not whether the guy dies, it's how fast he stops the fight. That is the only criteria to look at. Ask the ME, would the BG have expired sooner if the bullet pierced his heart? If the ME tells you diff, he should go back to school. I want the fight over sooner than later. A round that hits important vital organs is going to do that better than one that does not.
That may not be medical text book stuff, but pure common sense. Destroy the lungs or liver, the fight will eventually end, & w/o medical care, the wound is still mortal. You will just get killed in the time between. The FBI shooting is good proof of what happens when you don't get rounds into the important vitals. Is the 12"min the end all to be all, no, would a bullet going 10"-11" do just as well, maybe. I have no issue w/ a large volumn wound going 10", it will likely get the job done. Then again, big guy, lots of fat & muscle, oblique shot that has to go along way to hit the heart, maybe not. You have to draw a line someplace & that is as good as any.:dunno:

uz2bUSMC
11-02-2010, 12:16
The only way in which an animal or a man can be immediately and completely incapacitated, other than by severing the spinal cord at a high level, is by actual damage to the brain. The brain controls the muscles which maintain stance and movement and only if it is damaged in a way that prevents it maintaining the flow of nerve impulses to those muscles will the animal drop on the spot. A heart shot cannot do this because blood remaining in the brain and muscles maintains function for some 15 seconds or longer. Shots to other vital organs cannot do this because at best all they can do is deprive the brain of blood and that then takes some time to produce unconsciousness or semi consciousness. Those hunters who have shot an animal not in the head and not in the spine but have had the animal collapse as though the strings have been cut has to have prduced enough damage to the brain to achieve this effect.

Most hunters will have experienced somthing a little less dramatic in which the animal takes a few seconds to collapse but in which the blood loss could not account for such a rapid collapse. Sometimes the animal looks rather dazed, staggers around and then drops and in other cases it runs a short distance before collapsing. We all have a good idea what "immediate" means but these instances have to be caused by brain damage which is less than great enough to produce immediate incapacitation. The work of the Cortneys used 5 seconds as a cut off to separate such brain injury effects from blood loss effects and exclude animals that were hit in the heart or CNS by accident.

-There was another article I had come across in the past where a hunter describes the only boar he had ever lost. Accompanying this article was the video of the event. The boar was hit and fell like a sack of rocks and layed there, legs up, for what seemed to be at least 10 seconds... long enough for me to start thinking I was watching the wrong vid because I was sure the particular animal I was observing were done. Then it snapped to and took off into the brush, and by the hunter's account, tracking was unsuccessful.

Now, this particular animal was completely incapacitated... but it couldn't have been loss of blood pressure because you cannot recover from that and defenitely not a direct CNS hit because once again, there would be no recovery...

My speculation, not limited to me I am sure, is that the transmission is via large blood vessels. As the ballistic pressure wave passes through the body surrounding the bullet track, it stretches and compresses the tissue and collapses blood vessels as it does so. this acts like a pump which squirts blood throught the blood vessels in a massive pulse. It is some of that high pressure high velocity blood that cause the brain cell damage. More speculation of course!

-Even as the pressure reduces within the circ system the more distant from the source, it could have reached vessels that are to fragile to contain that pressure causing ruptures.
Now, speculation on speculation! If the above model is correct, the strength of that blood pulse is proportional to the volume of tissue in which the pressure gradient is sufficient to collapse large blood vessels within some restriced time. If this is so then not just the peak pressure but the duration of pressure is significant to the damage to the brain cells. From this I conclude that provided some limit of pressure is achieved and maintained over a distance of the bullet's track, the effect might be as great as where the peak pressure is higher but falls away more rapidly. That is, the significant measure of probability of suffidient brain cell damage might be the integral of pressure by the distance over which that presure exceeds some lower limit.

Just a thought!

English

,,,,,

BOGE
11-02-2010, 14:19
I am not disagreeing w/ the ME, just the staatement it was a fatal or mortal wound. That means little when the guy is still on his feet killing you. Like all the knobs out there that say this or that round has killed more people, blah, blah, blah. It's not whether the guy dies, it's how fast he stops the fight. That is the only criteria to look at. Ask the ME, would the BG have expired sooner if the bullet pierced his heart? If the ME tells you diff, he should go back to school. I want the fight over sooner than later. A round that hits important vital organs is going to do that better than one that does not.
That may not be medical text book stuff, but pure common sense. Destroy the lungs or liver, the fight will eventually end, & w/o medical care, the wound is still mortal. You will just get killed in the time between. The FBI shooting is good proof of what happens when you don't get rounds into the important vitals. Is the 12"min the end all to be all, no, would a bullet going 10"-11" do just as well, maybe. I have no issue w/ a large volumn wound going 10", it will likely get the job done. Then again, big guy, lots of fat & muscle, oblique shot that has to go along way to hit the heart, maybe not. You have to draw a line someplace & that is as good as any.:dunno:

Fred, accept the fact that not everyone falls over as if pole axed. There is NO perfect bullet. Feces happens. This ainīt turkey hunting. Some people simply don`t want to die easily. Youīre a big bullet fanatic so why didnīt Cole Younger die after being shot approx. 11 times in Northfield, MN? They werenīt using 9mm`s then.

NonPCnraRN
11-02-2010, 16:25
Incorrect. How many times does this BS have to be quashed. :upeyes: The wound in question was mortal. It wouldn`t have mattered it was a .50 BMG as the perp in question was RESOLUTE and wanted to kill and adrenaline is an an amazing drug.

It doesn`t matter if the bullet penetrates fully as the purpose of a gunshot wound is exsanguination (bleeding out), barring a CNS hit. You are diverting blood from its intended purpose. Nothing more, nothing less. If a person is bleeding into their own abdominal cavity from a gunshot wound it makes no difference if their are two holes or one. THE BLOOD IS NOT REACHING ITS INTENDED SOURCE, thereby shutting down the body (shock). Think about it.

I have seen people bleed out internally due to a dissecting aortic aneurysm. The amount of time ranged from many minutes to a few seconds depending on the extent of the rupture. I have seen esophageal varicies rupture and the patient bleed out as blood poured out of his mouth. Despite our best efforts the patient lasted less than a minute or two. You are correct that the cause of death is the loss of circulating blood volume to vital organs. However a large exit wound with a large amount of blood leaving will generally bleed out faster. With internal bleeding pressure builds up slowing the bleeding down depending on the elasticity of the compartment that the blood is leaking into. A sort of pressure equalibrium is reached slowing the blood loss down. Is that difference significant? That is almost impossible to answer as a large internal wound will bleed out faster than a small external wound. So for all practical purposes what you said is correct, blood loss is blood loss. Personally, I prefer a large exit wound with a blood trail Stevie Wonder could follow mixed with bits of organ tissue. I can quickly assess the extent of damage done vs internal bleeding. This applies more to a hunting situation vs SD. However I must admit such a wound in a BG tends to be reassuring in a SD situation. I would hope one will keep firing until the threat is neutralized regardless of whether exsanquination is internal or external.

fredj338
11-02-2010, 18:17
Fred, accept the fact that not everyone falls over as if pole axed. There is NO perfect bullet. Feces happens. This ainīt turkey hunting. Some people simply don`t want to die easily. Youīre a big bullet fanatic so why didnīt Cole Younger die after being shot approx. 11 times in Northfield, MN? They werenīt using 9mm`s then.
I think I outlined that earlier Boge; the bullet must hit vitals! Everything in the COM is not a vital. A big man has a bigger COM & more places to put bullets. As NonPC points out, internal bleeding is slower then when the body is leeking out of two or more holes. Oh yes, & back then, solid lead slugs, more like the puncture wounds I keep talking about. My dad was warden @ a state pen here. Comes home w/ pics of a guy stabbed 42 times w/ a shiv, 42 times! Yes he lived. So, again, the bullet must reach important vitals, the Cole younger shooting kinda supports that doesn't it?:supergrin:
A lung wound is mortal if not attended to, a gut shot is mortal if not attended to. Both can leave a guy in the fight for a very, very long time. Rupture any animals heart, 30sec max & the blood pressure drops to almost zero, animal falls over, fight or flight is done.