Warning, this is a long post, I'm not abridging it because I want to be very very clear. If you aren't into this kindof thing this article probably won't make you a fanatic. Although this is a good place to get a pretty good run-down if you're interested but don't know where to start.
Basic Mechanics of Terminal Ballistics
Contents
Introduction
Wound Concept
Incapacitation
Mechanisms of Tissue Damage
My Conclusion
Further Reading
Introduction-
There are some widely circulated beliefs about the effects of high speed projectiles on the human body. Some of these are true and some of them are misconceptions, not founded in the Laws of Physics but in preconceived notions and concepts circulated by popular media such as videogames and movies. This thread is an attempt to provide a source for clarification of the mechanics and factors of terminal ballistics and prevent myself from derailing any more threads. I do not claim to be a professional and of course my word is not law or fact. However I am a physics major and have been studying terminal ballistics and human anatomy and medicine for four years; this doesn't automaticly make me an authority on the subject, but it does carry a bit more credibility than media outlets designed for entertainment, note that this includes the Military channel and History channel. While comments of most any kind are completely welcome, keep in mind that if you're going to tell me I'm flat out wrong, you're going to need to supply some decent evidence, as everything in this article is based upon years of research. Though I will gladly change the article if it is established that I have misrepresented something or provided incorrect information.
Wound Concept-
Standard kinetic energy projectiles such as standard Full Metal Jacket bullets cause harm to a human by destroying organic tissue, damaged tissue may fail to perform its intended task and destroyed tissue certainly doesn't do its job. This can bee observed as multiple effects. Destroyed/damaged vascular tissue cannot hold blood and thus may cause harm through loss of blood volume and pressure. Destroyed/damaged neural tissue will not transmit the electrical signals of communication through the body. Destroyed/damaged muscular tissue poses a similar problem as it may not be able to exert and support force required for movement. Destroyed/damaged bone tissue can cause many problems including destruction of local tissue, loss of structural support, and cause of internal poisoning and Acute Stress Reaction, which can lead to circulatory shock. Destroyed/damaged respiratory tissue may result in loss of lung capacity, causing breathing issues, which may result in circulatory shock or even asphyxiation. Destruction of various organ structures can cause severe problems ranging from internal poisoning severe internal bleeding.
Incapacitation-
Incapacitation can result from:
Loss of consciousness, physical incapability to continue(hereby referred to as "physical incapacitation"), loss of drive to continue (know as psychological incapacitation), or death.
Loss of consciousness can be caused by circulatory shock, asphyxiation, neural trauma, and poisoning. Loss of consciousness may be short lived, but most people won't be fit to continue an offense after regaining consciousness.
Physical incapacitation is caused when the body is damaged to the point that persisting in given activity is rendered physically impossible due to damage to muscular and bone tissue, or damage to neural tissue, causing paralysis in relavent locations.
Psychological incapacitation is difficult to pin down, there are far too many factors to predict it or determine its exact causes. Psychological incapacitation may mean the person in question just gave up, maybe he/she intentionally stop his/her activity to make top priority of seeking medical attention, or maybe he/she just can't focus past the wound they've received. There are nearly infinite variables and they tend to be based on the mental state of the person in question.
Death or Brain Death can result from catastrophic destruction of vital structures such as the brain, effectively deleting the victim's being from existence, or it can simply result from severe blood loss and organ failure. This one's pretty intuitive.
Mechanisms of Tissue damage-
I. Mechanical crushing/Stretching of Tissue
This is simple, when a bullet strikes tissue at relatively high velocity, it pushes on the tissue, exerting energy into the tissue, causing it to stretch. As would be found in most any firearm projectile, sufficient projectile energy allows the projectile to continue to stretch the tissue until its elastic threshold has been passed, causing the tissue to tear to relieve tension; as the tissue tears, the projectile is granted access to the tissue beyond the torn tissue, the precess repeats as the projectile penetrates and the projectile is gradually ridden of it's kinetic energy, causing it to slow down, eventually to a stop, though many projectiles will penetrate completely through a human without running out of energy. This is the most basic concept of projectile damage; what tissue the bullet hits is damaged/destroyed.
II. Energy Transfer(Temporary Cavity)
When a bullet passes through a fluid medium (organic tissue) it faces fluid drag. Fluid drag causes kinetic energy to transfer to surrounding tissue, by nature this means that the surrounding tissue is "Pushed" away from the bullet radially, this is referred to as temporary cavity and can be observed as temporarily displaced tissue surrounding the path of the bullet.
This can be observed in great quantity on this channel http://ift.tt/1q6kJxh
*** I cannot stress this enough. This is NOT hydrostatic shock. ***
This phenomenon stretches tissue surrounding the bullet and not just that directly in front of the bullet this is based on how much energy the bullet transfers to the tissue, temporary cavity is often harmless and leaves flesh mostly unharmed, maybe slightly bruised.Another thing to consider is that a bullet traveling point first through tissue doesn't transfer much energy, no matter how fast it's traveling. If a bullet upsets(yaws, expands, fragments, deforms etc) fluid drag acting on the bullet is greatly increased, causing a significant local transfer of kinetic energy, which may potentially overcome the elastic threshold of the surrounding tissue and cause radial tears. In a study performed by the author of the channel linked above (who is a qualified professional) it was found that, upon upsetting, projectiles with roughly 1500 Joules of impact force can cause peripheral tissue disruption, with the effects increasing in intensity with increased impact force. Of course different types of tissue have different thresholds, for more information on this you should read the original article. It should also be noted this is not a property highly valued in military and law enforcement applications and is usually overlooked for other qualities. The most obvious case in which this effect presents itself is in the effects of Anti-Materiele projectiles on living creatures. Otherwise it's not vastly significant, but could be something to keep in mind.
III. Bow Shockwave
This is something that is debated heavily in the scientific community and it would be arrogant for me or anyone else not here to claim they know better than all those scientists having a world war over the issue.I can simply make observations about the concept. While it is something that has some merrit, it seems to be inconsistent. It can be observed in COM shots taken with high velocity (>2000fps) ammunition. It has been observed that people and animals can sometimes faint immediately upon impact of the projectile. This is theorized to be caused by high pressure shockwaves compressing neurral components located in the upper torse, causing temporary respiratory paralysis. It should be noted that this could also be explained by local energy transfer to the upper spinal column, which will have similar, or far more serious effects. One thing that I personally question about the concept, is that it does not scale proportionally with velocity, despite being linked to velocity; this can be observed in failed incapacitaion from anti-Materiele projectiles such as .50 BMG, and .408 Cheyenne tactical, whose muzzle velocity far exceeds those of most other rounds included in the 'high velocity' group. These failures to incapacitate result from the projectile failing to upset within tissue; this seems to point to energy transfer as the mechanism of action for these rounds. Another far more well known example is failure of 5.56 projectiles to incapacitate at close range (this also happens at long range but that is a different subject). They are reported to go straight through the enemy combatants leaving a very small wound, requiring more rounds on target to stop the enemy combatant. At such close range, the 5.56 round is traveling at a velocity of nearly or over 3000 fps, easily more than enough to be considered high velocity. If it were the velocity causing such deadly shockwaves, then the 5.56 round would be extremely effective at close range with a higher muzzle velocity that that of most full power rifle rounds. These are just some points to keep in mind.
IV. Hydrostatic Shock
This is also highly debated, same rules apply here.
Remember, this is not the big bubble you see in ballistic gel tests. Hydrostatic shock is the theory that high velocity projectiles can cause remote wounding effects. There have been events in the past three or so conflicts that the US has been in in which someone would die instantly from a shot to the chest, then it would be found later that the victim had severe brain hemorraging'; this has also been observed in animals. It has also been theorized that this is caused by a mass increase in blood pressure caused by something I've only ever heard called "Blood Hammer"; imagine water hammer but with blood. The concept is that a projectile strikes a sensitive vascular region as the heart beats, the force of the heart pumping, combined with the radial energy transfer from the projectile impact causes a spike in blood pressure, and the pressure is relieved somewhere in the body by a burst blood vessel.
I will not discuss this deeply but I express the same doubt about this phenomenon as I did about the previous; it is based on velocity but it would seem that high velocity itself does not cause injury.
(Also don't go to the wikipedia page on this; it's so biased it's not even funny, just don't go there.)
My conclusion-
I follow these findings to their logical conclusions. The conclusion is that guns don't knock people down like they do on TV. These finding may contradict what you believe about terminal ballistics, but keep in mind, there is much information spread around, it is spread around by videogames and stereotypes and people with a flawed view of the physical properties of the universe. Again, feel free to express distrust in this article, but please to so with logical reasoning and not because stereotypes tell you that loud guns always kill in one shot and that a rifle is more lethal than a handgun just because it is.
Liberate your mind :)
Further Reading-
These aren't exactly my sources, remember that I've been at this awhile, what I've found is from years and many many different websites and books; these are just a few websites and I couldn't find some of the really good ones.
http://ift.tt/1q6kLVT
http://ift.tt/1rOriHT
http://ift.tt/1q6kLVV
http://ift.tt/1q6kLVX
http://ift.tt/1rOriHY
http://ift.tt/1q6kMch
http://ift.tt/1q6kMci
Basic Mechanics of Terminal Ballistics
Contents
Introduction
Wound Concept
Incapacitation
Mechanisms of Tissue Damage
My Conclusion
Further Reading
Introduction-
There are some widely circulated beliefs about the effects of high speed projectiles on the human body. Some of these are true and some of them are misconceptions, not founded in the Laws of Physics but in preconceived notions and concepts circulated by popular media such as videogames and movies. This thread is an attempt to provide a source for clarification of the mechanics and factors of terminal ballistics and prevent myself from derailing any more threads. I do not claim to be a professional and of course my word is not law or fact. However I am a physics major and have been studying terminal ballistics and human anatomy and medicine for four years; this doesn't automaticly make me an authority on the subject, but it does carry a bit more credibility than media outlets designed for entertainment, note that this includes the Military channel and History channel. While comments of most any kind are completely welcome, keep in mind that if you're going to tell me I'm flat out wrong, you're going to need to supply some decent evidence, as everything in this article is based upon years of research. Though I will gladly change the article if it is established that I have misrepresented something or provided incorrect information.
Wound Concept-
Standard kinetic energy projectiles such as standard Full Metal Jacket bullets cause harm to a human by destroying organic tissue, damaged tissue may fail to perform its intended task and destroyed tissue certainly doesn't do its job. This can bee observed as multiple effects. Destroyed/damaged vascular tissue cannot hold blood and thus may cause harm through loss of blood volume and pressure. Destroyed/damaged neural tissue will not transmit the electrical signals of communication through the body. Destroyed/damaged muscular tissue poses a similar problem as it may not be able to exert and support force required for movement. Destroyed/damaged bone tissue can cause many problems including destruction of local tissue, loss of structural support, and cause of internal poisoning and Acute Stress Reaction, which can lead to circulatory shock. Destroyed/damaged respiratory tissue may result in loss of lung capacity, causing breathing issues, which may result in circulatory shock or even asphyxiation. Destruction of various organ structures can cause severe problems ranging from internal poisoning severe internal bleeding.
Incapacitation-
Incapacitation can result from:
Loss of consciousness, physical incapability to continue(hereby referred to as "physical incapacitation"), loss of drive to continue (know as psychological incapacitation), or death.
Loss of consciousness can be caused by circulatory shock, asphyxiation, neural trauma, and poisoning. Loss of consciousness may be short lived, but most people won't be fit to continue an offense after regaining consciousness.
Physical incapacitation is caused when the body is damaged to the point that persisting in given activity is rendered physically impossible due to damage to muscular and bone tissue, or damage to neural tissue, causing paralysis in relavent locations.
Psychological incapacitation is difficult to pin down, there are far too many factors to predict it or determine its exact causes. Psychological incapacitation may mean the person in question just gave up, maybe he/she intentionally stop his/her activity to make top priority of seeking medical attention, or maybe he/she just can't focus past the wound they've received. There are nearly infinite variables and they tend to be based on the mental state of the person in question.
Death or Brain Death can result from catastrophic destruction of vital structures such as the brain, effectively deleting the victim's being from existence, or it can simply result from severe blood loss and organ failure. This one's pretty intuitive.
Mechanisms of Tissue damage-
I. Mechanical crushing/Stretching of Tissue
This is simple, when a bullet strikes tissue at relatively high velocity, it pushes on the tissue, exerting energy into the tissue, causing it to stretch. As would be found in most any firearm projectile, sufficient projectile energy allows the projectile to continue to stretch the tissue until its elastic threshold has been passed, causing the tissue to tear to relieve tension; as the tissue tears, the projectile is granted access to the tissue beyond the torn tissue, the precess repeats as the projectile penetrates and the projectile is gradually ridden of it's kinetic energy, causing it to slow down, eventually to a stop, though many projectiles will penetrate completely through a human without running out of energy. This is the most basic concept of projectile damage; what tissue the bullet hits is damaged/destroyed.
II. Energy Transfer(Temporary Cavity)
When a bullet passes through a fluid medium (organic tissue) it faces fluid drag. Fluid drag causes kinetic energy to transfer to surrounding tissue, by nature this means that the surrounding tissue is "Pushed" away from the bullet radially, this is referred to as temporary cavity and can be observed as temporarily displaced tissue surrounding the path of the bullet.
This can be observed in great quantity on this channel http://ift.tt/1q6kJxh
*** I cannot stress this enough. This is NOT hydrostatic shock. ***
This phenomenon stretches tissue surrounding the bullet and not just that directly in front of the bullet this is based on how much energy the bullet transfers to the tissue, temporary cavity is often harmless and leaves flesh mostly unharmed, maybe slightly bruised.Another thing to consider is that a bullet traveling point first through tissue doesn't transfer much energy, no matter how fast it's traveling. If a bullet upsets(yaws, expands, fragments, deforms etc) fluid drag acting on the bullet is greatly increased, causing a significant local transfer of kinetic energy, which may potentially overcome the elastic threshold of the surrounding tissue and cause radial tears. In a study performed by the author of the channel linked above (who is a qualified professional) it was found that, upon upsetting, projectiles with roughly 1500 Joules of impact force can cause peripheral tissue disruption, with the effects increasing in intensity with increased impact force. Of course different types of tissue have different thresholds, for more information on this you should read the original article. It should also be noted this is not a property highly valued in military and law enforcement applications and is usually overlooked for other qualities. The most obvious case in which this effect presents itself is in the effects of Anti-Materiele projectiles on living creatures. Otherwise it's not vastly significant, but could be something to keep in mind.
III. Bow Shockwave
This is something that is debated heavily in the scientific community and it would be arrogant for me or anyone else not here to claim they know better than all those scientists having a world war over the issue.I can simply make observations about the concept. While it is something that has some merrit, it seems to be inconsistent. It can be observed in COM shots taken with high velocity (>2000fps) ammunition. It has been observed that people and animals can sometimes faint immediately upon impact of the projectile. This is theorized to be caused by high pressure shockwaves compressing neurral components located in the upper torse, causing temporary respiratory paralysis. It should be noted that this could also be explained by local energy transfer to the upper spinal column, which will have similar, or far more serious effects. One thing that I personally question about the concept, is that it does not scale proportionally with velocity, despite being linked to velocity; this can be observed in failed incapacitaion from anti-Materiele projectiles such as .50 BMG, and .408 Cheyenne tactical, whose muzzle velocity far exceeds those of most other rounds included in the 'high velocity' group. These failures to incapacitate result from the projectile failing to upset within tissue; this seems to point to energy transfer as the mechanism of action for these rounds. Another far more well known example is failure of 5.56 projectiles to incapacitate at close range (this also happens at long range but that is a different subject). They are reported to go straight through the enemy combatants leaving a very small wound, requiring more rounds on target to stop the enemy combatant. At such close range, the 5.56 round is traveling at a velocity of nearly or over 3000 fps, easily more than enough to be considered high velocity. If it were the velocity causing such deadly shockwaves, then the 5.56 round would be extremely effective at close range with a higher muzzle velocity that that of most full power rifle rounds. These are just some points to keep in mind.
IV. Hydrostatic Shock
This is also highly debated, same rules apply here.
Remember, this is not the big bubble you see in ballistic gel tests. Hydrostatic shock is the theory that high velocity projectiles can cause remote wounding effects. There have been events in the past three or so conflicts that the US has been in in which someone would die instantly from a shot to the chest, then it would be found later that the victim had severe brain hemorraging'; this has also been observed in animals. It has also been theorized that this is caused by a mass increase in blood pressure caused by something I've only ever heard called "Blood Hammer"; imagine water hammer but with blood. The concept is that a projectile strikes a sensitive vascular region as the heart beats, the force of the heart pumping, combined with the radial energy transfer from the projectile impact causes a spike in blood pressure, and the pressure is relieved somewhere in the body by a burst blood vessel.
I will not discuss this deeply but I express the same doubt about this phenomenon as I did about the previous; it is based on velocity but it would seem that high velocity itself does not cause injury.
(Also don't go to the wikipedia page on this; it's so biased it's not even funny, just don't go there.)
My conclusion-
I follow these findings to their logical conclusions. The conclusion is that guns don't knock people down like they do on TV. These finding may contradict what you believe about terminal ballistics, but keep in mind, there is much information spread around, it is spread around by videogames and stereotypes and people with a flawed view of the physical properties of the universe. Again, feel free to express distrust in this article, but please to so with logical reasoning and not because stereotypes tell you that loud guns always kill in one shot and that a rifle is more lethal than a handgun just because it is.
Liberate your mind :)
Further Reading-
These aren't exactly my sources, remember that I've been at this awhile, what I've found is from years and many many different websites and books; these are just a few websites and I couldn't find some of the really good ones.
http://ift.tt/1q6kLVT
http://ift.tt/1rOriHT
http://ift.tt/1q6kLVV
http://ift.tt/1q6kLVX
http://ift.tt/1rOriHY
http://ift.tt/1q6kMch
http://ift.tt/1q6kMci
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