Hydrostatic shock... - Tilted Forum Project Discussion Community

ziadel · 03-09-2005, 03:54 PM

this was originally gonna get stuck in the Deagle thread, but I felt it warranted its own thread...

Quote:

Originally Posted by longbough

And, believe it or not, a heavier, faster bullet doesn't necessarily mean more tissue damage or bigger wound. Over-powered projectiles tend to go through soft tissue and overpenetrate the target. The most incapacitating wound is made when a round stops in the target delivering all it's energy by either mushrooming or fragmenting. Shooting cinder blocks is one thing. Shooting live targets is another.

a larger bullet means more tissue damage, lets say for ease of comparison we have a 9mm fmj and a .50AE fmj both shot at people

they'll both punch straight through, the only difference is the .50 will leave a half inch sized hole (roughly) and the 9 a 9mm hole.. since .50 is bigger than 9mm that just might mean more tissue damage... Faster projectiles? Larger temporary crush cavity and hydrostatic shock...

Now, thats not really relevant, but then you started talking about Hydrostatic shock, for those of you that are lost, longbough stated that the best round stops in the target, transferring all of its enegery to the target (thats not exactly what he said, but bullets don't mushroom to transfer energy, they mushroom or fragment to destroy more tissue, thats the main reason that and to stop over-penetration) he's talking about hydrostatic shock, which is the theory that when a bullet enters a living creature it creates a shock wave within the creatures body, which is supposed to be what causes quick kills. Hydrostatic shock, in my opinion, is bunk, ESPECIALLY if you think it's going to happen at handgun energy levels.
Why is it called Hydrostatic shock? Because the shock wave is said to be conducted by water, which we are 89% (I think) comprised of...

so what kills things?

depriving the brain of oxygen (blood loss)
damage to the central nervous system
damage to the vital organs
any combination or 2 or more things I have listed..

If we are talking about straight Full Metal Jacket ammo, the odds of damaging something our target NEEDS to have to live increases by using a bigger bullet.

this was kind of a rant and I am sure it's not easy to follow, so please, don't spare any questions...

Cylvre · 03-09-2005, 05:56 PM

Actually hydostatic shock isn't bunk, and it does happen at handgun level energy levels. I'm currently in training for becoming an EMT, I've got several instructors and the topic of hydrostatic shock came up in one of out classes. I tend to believe them in this case because one was in the militry for many years and the other worked law enforcement, many years of out of Reno.

First of all the way your describing hydrostatic shock is miseading:

Quote:

Originally Posted by ziadel

the theory that when a bullet enters a living creature it creates a shock wave within the creatures body, which is supposed to be what causes quick kills

Think of it like this: get yourself a bowl of water, now take a marble or really anything of the sort and drop it in the middle of the bowl. You'll see ripples form in the water. Now that is the basic idea behind two things: 1) Blood Pressure (which is a measure of the pressure of the wave of blood that the heart causes when it beats) and 2) Hydrostatic shock. If you were to drop a larger object in the bowl you'd obviously get larger waves.

Like I said, that's how I understand it and I'm certainly not a doctor so I may be wrong.

I do agree with you about the fact that hydrostatic shock alone does not make for a quick kill. What hydrostatic shock does do is increase stopping power by causing more pain, or so I would imagine. It may be attributed to quicker kills because of the fact that I'm sure it causes more issue damage with possible internal bleeding.

longbough · 03-10-2005, 11:49 AM

Funny you should mention it. I am a doctor of Internal Medicine and I also study defensive shooting. I'll give my opinion on the matter and digress into some other issues on my mind.

Certainly a faster, heavier projectile carries more kinetic energy than a smaller, slower one. However, if a projectile is powerful enough to pass through a target it will not transfer all of its energy into the target (i.e. damage). That’s simple physics. A projectile that stops in a target will. I wouldn’t compare a 9mm to a 50 AE. That wasn’t my intent. But the efficacy of a handgun bullet is not about its ability to kill, but to incapacitate.

Hydrostatic shock may be a bit of a misnomer but it is a real phenomenon. Its importance lies in the ability to help “incapacitate” a target – not to kill a target. This is why JHPs are more effective than ball ammo for defense.

But let’s address some basic misconceptions first.

With the exception of a good, penetrating head-shot a handgun bullet is rarely capable of killing someone on the spot. But the sole objective of using a gun in defense is not to "kill" but to “stop” a target which presents an imminent threat. Two shots from a .45 to a chest has a high probability of stopping a subject only because of the neurological shock from acute traumatic injury to vital organs such as the heart and lungs. The phenomenon of “hydrostatic shock” contributes to the ability to deliver neurological shock. While such injuries may eventually result in death the immediate result, in most cases, is an incapacitated target that is no longer a threat.

So what makes an effective handgun caliber? One that is most successful at incapacitating a target – death and morbidity are just potential complications of stopping the subject.

Since I’m on the subject I might as well cover a few other myths that come up constantly about the defensive handgun:

#1. “The cops didn’t have to shoot the subject 41 times.” Yes and no. Putting aside the unfortunate circumstances of that scenario let’s just consider the tactical perspective of the shooter. If a target’s body doesn't produce a reflexive neurocirculatory collapse after two rounds to the chest then the subject will still be standing. How can this happen? Under great stress extreme levels of epinephrine in an individual might be enough to “protect” them from shock. In a sense it acts to "override" the reflexive response. Often the subject is oblivious to the fact that they've been shot. The simple rule is that, if those first two rounds don’t stop a threat, then the next one will have to be to the head. (i.e. a killing shot)

Contrary to popular belief, punching holes into a torso with bullets is an inefficient way to kill a person. A human being is not made up of hitpoints – human physiology and pathophysiology is much more complex.

Modern defensive handgun technique drill is two shots to the thorax. And if the target remains a threat then a follow-up head shot.

Then why don't cops then go for the "head shot" after a failure to stop from thoracic hits? Police officers are trained to shoot center of mass because it’s an easier target. Consistent head shots under stress require a higher degree of training. I wonder if it’d also be “politically incorrect” for the public to know that a cop is trained to deliver head-shots. But the point is- while COM shots can be 96% effective there’s still 4% left standing.

#2. “Psychopaths and psychotic-druggies are supermen.” It should be no surprise that COM shots are less likely to stop a raging nut because their nervous response is likely blunted from all that epinephrine. But, in a defensive situation against a psycho, you should at least try to hit the chest first. It's still effective in most cases.

#3 “Why not shoot them (people) in the leg?” I hear this question all the time. Shooting the leg is a lousy idea. Let’s start with the basics:
a. A leg shot does not have a high probability of stopping someone. It is less likely to induce neurologic shock than a chest shot (see above) and, contrary to popular belief, does not render the leg muscles useless in most cases.
b. A leg is a harder shot under stress.
c. Should the bullet hit the big femoral artery near the groin the person may bleed a great deall. While the bleeding itself may cause morbidity it will happen over a longer period of time. In the meanwhile they’re still a threat to you until the blood-loss catches up to them.

People appalled by this rationale see it as a justification for killing. Not true. Here’s the part that people (gun-owners and non-gun-owners) should understand:

Only in a situation that requires you stop an imminent threat by violent means should you even present (draw) your firearm. This means that a gun should not be brandished “as a threat” or used in an encounter where such a threat is non-existent (Your opinion may be different but this is how I was trained and is what I believe). If you are armed and you see someone stealing your car - just let it go. By any responsible standard only a complete moron would draw their weapon. Leave it to your insurance.

However, if someone is charging at you with the intent of strangling you then, as long as you feel your life is threatened you would be justified in using your weapon to defend yourself in the fashion consistent with your training. It doesn’t matter if the other person has a weapon. This doesn’t mean you HAVE TO draw your weapon, either. The choice is yours But if you draw it - USE IT!

Let's recap:

1. Don't even present a gun unless you're going to use it.
2. Only use it in the case of imminent mortal danger to you or a loved one.
3. To use it properly put two quick shots (4-5inches apart is optimal) to the thoracic region (chest).
4. If the subject is still a threat then place the next round right between the eyes (Do not shoot the forhead - the frontal portion of the skull is very hard - penetration will likely be suboptimal and a glancing shot can easily ricochet off the skull).

Forgive the digression, but I hope that helps.

longbough · 03-10-2005, 12:27 PM

BTW, Ziadel, I noticed you quote Jeff Cooper in another thread.
As a matter of fact, all the principles I've described are fundamental to the modern defensive handgun as taught by Col Jeff Cooper at Gunsite.

I'm no advocate of the 9mm. I'd rather trust my life with my .45 USP Compact or my .40 Glock 23. The "stopping power" of the .45 is a function of its larger diameter which results is a greater degree of "shock" should the bullet remain in the target. That's the current rationale. The size of the cavity is not the primary factor.

Now, I wasn't saying that a .50AE won't stop a subject. A .50AE is potentially more effective provided it doesn't overpenetrate the target - but I'm not sure that's the case. That's all.

Remember the 10mm? That was a big bullet with a hot load. It was considered, in the 80s, to be the ultimate defensive round. Compared to, say, the .40S&W it certainly has superior penetration and kinetic energy and ballistics, but the statistics show (in real world LEO encounters) that the 10mm had poor "one shot stop" percentages (81-82% one shot stop for 10mm and 87-96% for the .40). The 10mm was even less effective in the "one shot stop" as compared to the 9mm (79-91%)! The FBI's initial rationale for considering the 10mm was their desire to optimize penetration through barriers, doors and vehicles.

The same database of LEO encounters show that the .44 magnum (76-90% one shot stop) is an inferior defense round than the .357 magnum (87-96%) due to its tendency to overpenetrate. I'm willing to bet the .50AE would do likewise.

So I stand by my earlier statement - "Shooting cinder blocks is one thing. Shooting live targets is another." Kinetic energy is only part of the equation when it comes to stopping power.

bubonico · 03-31-2005, 11:07 PM

longbough- You seem to be very knowledgeable on the topic so I hope you don't mind answering a quick question for me. I've always understood that the damage done by a bullet is primarily a matter of how much energy is released into the body. What I'm wondering is if a 9x19 and .45 ACP would do roughly the same amount of damage if both were hollowpoints. I may be mistaken but I think they have roughly the same amount of muzzle energy. Will the physical damage caused by the .45 make that much of a difference? It seems to me that a .45 and 9mm should do about the same amount of damage to a person supposing neither exits the body. On a side note, from a military standpoint we must use full metal jacket ammunition I've been thoroughly disapointed with the stopping power of my issue 9mm. I'd be quite enthused if I were allowed to carry my USP .45.

MrTuffPaws · 03-31-2005, 11:48 PM

^^^^^^^
At pistol velocities, hydrostatics don't do near as much damage as rifle rounds. For a pistol round, it is shot placement and penetration that counts the most.

longbough · 04-07-2005, 09:02 AM

MrTuffPaws is correct. Especially with handgun rounds - shot placement is the most critical factor in defensive shooting. In my mind I try to think of shot placement as a lot like stabbing someone with a sharp pencil (sorry about the gruesome image but shooting isn't much prettier). You can stab someone 20 times in all the wrong spots or just once in the right spot to stop them. That's why constant range practice is so important - otherwise the handgun just gives a false sense of security.

As I recall, the .45 ACP still has much more kinetic energy than the 9mm. Kinetic energy is a function of both mass and velocity. While the 9mm is faster the .45 has more than enough mass to outclass the 9mm - even if they were both hollow points.

But, regardless of the numbers and calculations, and ballistic tests the real facts are in the empirical data taken from the field. The muzzle velocity, terminal ballistics and other numbers on paper are all theoretical until the performance of the round is tested in "real" encounters. Since (thankfully) I've never had to shoot someone I can't tell you from personal experience. But the experts and professionals I've met tell me that the .45 is noticably more effective at stopping a subject. And the empirical data support that claim.

In fact my numbers were culled from a resource that breaks the data down even further by ammunition manufacturer (PMC, Corbon, Federal Hydra-Shok, etc.) and bullet configuration (FMJ,JHP, etc.). They also show the .45ACP to be a better bullet. And, yes, the JHP is a more effective stopper than FMJ.

I'd take a good 1911 or USP.45 over any 9mm any day of the week. If I haven't mentioned it before - the 9mm and .38special are bareley "acceptable" for defense as handgun rounds. The .380, .22, .32, .25acp are regarded as inappropriate - but "better than nothing." So I'd avoid these if I could.

I hope that answers your question.

03-10-2005, 11:49 AM	#3 (permalink)
longbough Soylent Green is people. Location: Northern California	Funny you should mention it. I am a doctor of Internal Medicine and I also study defensive shooting. I'll give my opinion on the matter and digress into some other issues on my mind. Certainly a faster, heavier projectile carries more kinetic energy than a smaller, slower one. However, if a projectile is powerful enough to pass through a target it will not transfer all of its energy into the target (i.e. damage). That’s simple physics. A projectile that stops in a target will. I wouldn’t compare a 9mm to a 50 AE. That wasn’t my intent. But the efficacy of a handgun bullet is not about its ability to kill, but to incapacitate. Hydrostatic shock may be a bit of a misnomer but it is a real phenomenon. Its importance lies in the ability to help “incapacitate” a target – not to kill a target. This is why JHPs are more effective than ball ammo for defense. But let’s address some basic misconceptions first. With the exception of a good, penetrating head-shot a handgun bullet is rarely capable of killing someone on the spot. But the sole objective of using a gun in defense is not to "kill" but to “stop” a target which presents an imminent threat. Two shots from a .45 to a chest has a high probability of stopping a subject only because of the neurological shock from acute traumatic injury to vital organs such as the heart and lungs. The phenomenon of “hydrostatic shock” contributes to the ability to deliver neurological shock. While such injuries may eventually result in death the immediate result, in most cases, is an incapacitated target that is no longer a threat. So what makes an effective handgun caliber? One that is most successful at incapacitating a target – death and morbidity are just potential complications of stopping the subject. Since I’m on the subject I might as well cover a few other myths that come up constantly about the defensive handgun: #1. “The cops didn’t have to shoot the subject 41 times.” Yes and no. Putting aside the unfortunate circumstances of that scenario let’s just consider the tactical perspective of the shooter. If a target’s body doesn't produce a reflexive neurocirculatory collapse after two rounds to the chest then the subject will still be standing. How can this happen? Under great stress extreme levels of epinephrine in an individual might be enough to “protect” them from shock. In a sense it acts to "override" the reflexive response. Often the subject is oblivious to the fact that they've been shot. The simple rule is that, if those first two rounds don’t stop a threat, then the next one will have to be to the head. (i.e. a killing shot) Contrary to popular belief, punching holes into a torso with bullets is an inefficient way to kill a person. A human being is not made up of hitpoints – human physiology and pathophysiology is much more complex. Modern defensive handgun technique drill is two shots to the thorax. And if the target remains a threat then a follow-up head shot. Then why don't cops then go for the "head shot" after a failure to stop from thoracic hits? Police officers are trained to shoot center of mass because it’s an easier target. Consistent head shots under stress require a higher degree of training. I wonder if it’d also be “politically incorrect” for the public to know that a cop is trained to deliver head-shots. But the point is- while COM shots can be 96% effective there’s still 4% left standing. #2. “Psychopaths and psychotic-druggies are supermen.” It should be no surprise that COM shots are less likely to stop a raging nut because their nervous response is likely blunted from all that epinephrine. But, in a defensive situation against a psycho, you should at least try to hit the chest first. It's still effective in most cases. #3 “Why not shoot them (people) in the leg?” I hear this question all the time. Shooting the leg is a lousy idea. Let’s start with the basics: a. A leg shot does not have a high probability of stopping someone. It is less likely to induce neurologic shock than a chest shot (see above) and, contrary to popular belief, does not render the leg muscles useless in most cases. b. A leg is a harder shot under stress. c. Should the bullet hit the big femoral artery near the groin the person may bleed a great deall. While the bleeding itself may cause morbidity it will happen over a longer period of time. In the meanwhile they’re still a threat to you until the blood-loss catches up to them. People appalled by this rationale see it as a justification for killing. Not true. Here’s the part that people (gun-owners and non-gun-owners) should understand: Only in a situation that requires you stop an imminent threat by violent means should you even present (draw) your firearm. This means that a gun should not be brandished “as a threat” or used in an encounter where such a threat is non-existent (Your opinion may be different but this is how I was trained and is what I believe). If you are armed and you see someone stealing your car - just let it go. By any responsible standard only a complete moron would draw their weapon. Leave it to your insurance. However, if someone is charging at you with the intent of strangling you then, as long as you feel your life is threatened you would be justified in using your weapon to defend yourself in the fashion consistent with your training. It doesn’t matter if the other person has a weapon. This doesn’t mean you HAVE TO draw your weapon, either. The choice is yours But if you draw it - USE IT! Let's recap: 1. Don't even present a gun unless you're going to use it. 2. Only use it in the case of imminent mortal danger to you or a loved one. 3. To use it properly put two quick shots (4-5inches apart is optimal) to the thoracic region (chest). 4. If the subject is still a threat then place the next round right between the eyes (Do not shoot the forhead - the frontal portion of the skull is very hard - penetration will likely be suboptimal and a glancing shot can easily ricochet off the skull). Forgive the digression, but I hope that helps. Last edited by longbough; 03-10-2005 at 04:25 PM..

03-10-2005, 12:27 PM	#4 (permalink)
longbough Soylent Green is people. Location: Northern California	BTW, Ziadel, I noticed you quote Jeff Cooper in another thread. As a matter of fact, all the principles I've described are fundamental to the modern defensive handgun as taught by Col Jeff Cooper at Gunsite. I'm no advocate of the 9mm. I'd rather trust my life with my .45 USP Compact or my .40 Glock 23. The "stopping power" of the .45 is a function of its larger diameter which results is a greater degree of "shock" should the bullet remain in the target. That's the current rationale. The size of the cavity is not the primary factor. Now, I wasn't saying that a .50AE won't stop a subject. A .50AE is potentially more effective provided it doesn't overpenetrate the target - but I'm not sure that's the case. That's all. Remember the 10mm? That was a big bullet with a hot load. It was considered, in the 80s, to be the ultimate defensive round. Compared to, say, the .40S&W it certainly has superior penetration and kinetic energy and ballistics, but the statistics show (in real world LEO encounters) that the 10mm had poor "one shot stop" percentages (81-82% one shot stop for 10mm and 87-96% for the .40). The 10mm was even less effective in the "one shot stop" as compared to the 9mm (79-91%)! The FBI's initial rationale for considering the 10mm was their desire to optimize penetration through barriers, doors and vehicles. The same database of LEO encounters show that the .44 magnum (76-90% one shot stop) is an inferior defense round than the .357 magnum (87-96%) due to its tendency to overpenetrate. I'm willing to bet the .50AE would do likewise. So I stand by my earlier statement - "Shooting cinder blocks is one thing. Shooting live targets is another." Kinetic energy is only part of the equation when it comes to stopping power. Last edited by longbough; 03-10-2005 at 01:48 PM..

03-31-2005, 11:07 PM	#5 (permalink)
bubonico Upright Location: Iraq :(	longbough- You seem to be very knowledgeable on the topic so I hope you don't mind answering a quick question for me. I've always understood that the damage done by a bullet is primarily a matter of how much energy is released into the body. What I'm wondering is if a 9x19 and .45 ACP would do roughly the same amount of damage if both were hollowpoints. I may be mistaken but I think they have roughly the same amount of muzzle energy. Will the physical damage caused by the .45 make that much of a difference? It seems to me that a .45 and 9mm should do about the same amount of damage to a person supposing neither exits the body. On a side note, from a military standpoint we must use full metal jacket ammunition I've been thoroughly disapointed with the stopping power of my issue 9mm. I'd be quite enthused if I were allowed to carry my USP .45. __________________ "People sleep peacably in their beds at night only because rough men stand ready to do violence on their behalf" -George Orwell

03-31-2005, 11:48 PM	#6 (permalink)
MrTuffPaws Addict Location: NorCal	^^^^^^^ At pistol velocities, hydrostatics don't do near as much damage as rifle rounds. For a pistol round, it is shot placement and penetration that counts the most.

04-07-2005, 09:02 AM	#7 (permalink)
longbough Soylent Green is people. Location: Northern California	MrTuffPaws is correct. Especially with handgun rounds - shot placement is the most critical factor in defensive shooting. In my mind I try to think of shot placement as a lot like stabbing someone with a sharp pencil (sorry about the gruesome image but shooting isn't much prettier). You can stab someone 20 times in all the wrong spots or just once in the right spot to stop them. That's why constant range practice is so important - otherwise the handgun just gives a false sense of security. As I recall, the .45 ACP still has much more kinetic energy than the 9mm. Kinetic energy is a function of both mass and velocity. While the 9mm is faster the .45 has more than enough mass to outclass the 9mm - even if they were both hollow points. But, regardless of the numbers and calculations, and ballistic tests the real facts are in the empirical data taken from the field. The muzzle velocity, terminal ballistics and other numbers on paper are all theoretical until the performance of the round is tested in "real" encounters. Since (thankfully) I've never had to shoot someone I can't tell you from personal experience. But the experts and professionals I've met tell me that the .45 is noticably more effective at stopping a subject. And the empirical data support that claim. In fact my numbers were culled from a resource that breaks the data down even further by ammunition manufacturer (PMC, Corbon, Federal Hydra-Shok, etc.) and bullet configuration (FMJ,JHP, etc.). They also show the .45ACP to be a better bullet. And, yes, the JHP is a more effective stopper than FMJ. I'd take a good 1911 or USP.45 over any 9mm any day of the week. If I haven't mentioned it before - the 9mm and .38special are bareley "acceptable" for defense as handgun rounds. The .380, .22, .32, .25acp are regarded as inappropriate - but "better than nothing." So I'd avoid these if I could. I hope that answers your question.