.40 Caliber Pressure Wave Effects
- Thread starter Michael Courtney
- Start date
- Status
Those were Federal EFMJs, which exhibit a much lower weight and lower velocity than 99% of conventional hollowpoints, much poorer expansion reliability, and have a rubber tip. Not exactly representative of an entire caliber. Even a .22 pistol will shoot through a dozen layers of thick cloth, as long as you're using bullets made of lead.
Michael Courtney
Member
I should mention that our motive in our ballistic research is not to benefit any particular gun industry interest, but rather to make our results widely available and easily repeatable so that the appropriate gun industry interests will apply our scientific results to the development of more effective products.
Our interest goes beyond terminal ballistics.
We've got a separate project that shows that reducing barrel friction can increase bullet energy by 100 ft-lbs in service cartridges.
In yet another project we have developed methods for measuring bullet velocity and ballistic coefficients with a PC soundcard to enable more ammunition users to compare manufacturers specifications to the reality of their own guns. We hope that one or more of the chronograph manufacturers will productize this idea.
We are also developing forensic techniques for reconstructing gun fights from audio recordings of the event. With the increasing amount of audio surveillance, an increasing number of shooting events are being recorded. Precise time reconstruction of shooting events should allow for incapacitation theories to be quantitatively tested, so the gun industry interests will have a much better idea which incapacitation theories are accurate in considering future designs.
Michael Courtney
Our interest goes beyond terminal ballistics.
We've got a separate project that shows that reducing barrel friction can increase bullet energy by 100 ft-lbs in service cartridges.
In yet another project we have developed methods for measuring bullet velocity and ballistic coefficients with a PC soundcard to enable more ammunition users to compare manufacturers specifications to the reality of their own guns. We hope that one or more of the chronograph manufacturers will productize this idea.
We are also developing forensic techniques for reconstructing gun fights from audio recordings of the event. With the increasing amount of audio surveillance, an increasing number of shooting events are being recorded. Precise time reconstruction of shooting events should allow for incapacitation theories to be quantitatively tested, so the gun industry interests will have a much better idea which incapacitation theories are accurate in considering future designs.
Michael Courtney
Borachon
Member
Wouldn't be my first time. But you really need to direct your wrath toward the person who told all those horrible lies about your "wonder weapon". So give those cops up in Michigan a call and tell them that you'd like to meet them in an open field because you're upset about all the lies they told that newspaper reporter. I'm just the messenger.
And oh, by the way, sounds like pissin' you off ain't so hard to do. Me..I've got a short fuse myself. We'd be well-matched.
Point I was trying to make before it got personal, is that you can talk all day (and I have before) about the merits of caliber, bullet weight, type of powder to use, hollowpoint vs FMJ vs Glaser vs frangible and go all the way around the world and still come back to the fact that you are shooting a weapon that no right thinking person would ever consider as their main line of defense in a war. People survive being shot in wars all the time. War rifles are much more powerful than pistols. Talking about which cheesy light-weight pop gun can out perform another cheesy pop gun is moving deck chairs on the Titanic.
Accuracy, economy of movement, familiarity with the performance and maintanence of your pistol. Everything else is chair moving.
Borachon
Member
No offense...but you had to do a STUDY to figure that out? Frictionless environments are going to produce faster moving objects...thus increasing energy output because of decreased lost momentum.
Kind of a no-brainer.
Michael Courtney
Member
Borachon said:
It is a no brainer that reducing friction will increase energy, but the important result is quantifying how much the energy can be increased. If reducing barrel friction would only increase bullet energy by 5-10 ft-lbs, I don't think anyone in the gun industry would bother. However, increasing energy by 100 ft-lbs is like stepping up to the next larger cartridge case in a given caliber, and might be significant enough to stimulate development activity.
The gun industry has temporarily plataued in terms of figuring out how to improve incapacitation from a pistol. Personally, I believe that within the next 25 years, we can see new designs that will make pistols as effective in incapacitating as the .223 is today.
Some of the gains in effectiveness will be incremental, such as gaining 100 ft-lbs of additional energy by reducing friction, a bullet that doesn't begin to expand at all until it has penetrated 3" or so (so more energy can be transferred closer to the vital organs, creating a larger pressure wave where it will do the most good), or a bullet design that creates a more intense pressure wave by a focussing effect (like a gain antenna focuses an RF wave).
Other gains in pistol bullet effectiveness will be in more revolutionary techniques, perhaps including:
1. An electrical effect, perhaps charging a capacitor to deliver a good shock on impact, or magnitizing the bullet. A changing magnetic field produces a current in a conducting medium. Body fluids are sufficiently conducting that impact by a magnetic bullet will produce a current.
2. A drug-related effect. This is going to be a hard sell politically, but if a drug can be developped that both provides very rapid incapacitation and increases the ultimate survivability, it may be politically viable, especially if the need is recognized to glean information from terrorists.
3. Explosive bullets designed to explode after penetrating a specified depth. We know exactly how to create TSC's and pressure waves as large as rifle bullets from pistol cartridges, 20 grains of explosive charge will easily do the trick.
4. Bullets that reach rifle velocities by continuing to accelerate after leaving the barrel. Of course, what you're really designing is a little rocket.
Currently, the liability and PR/political issues make these more revolutionary ideas impractical. However, there are only so many terrorist attacks/active shooter situatons that our collective political will can tolerate before we seek to at least arm our police and military with more effective handguns.
Michael Courtney
carolinaman
Member
Hi there Mr. Courtney,
I have been reading all of your posts with thoughtful and considerable interest and wish to know if you think that the fnfiveSeven cartridge is quite approaching what you have suggested a "gun industry search for a rifle velocity cartridge in a handgun"?
Best,
Chris
I have been reading all of your posts with thoughtful and considerable interest and wish to know if you think that the fnfiveSeven cartridge is quite approaching what you have suggested a "gun industry search for a rifle velocity cartridge in a handgun"?
Best,
Chris
Michael Courtney
Member
carolinaman said:
Apart from penetrating kevlar, rifle velocities are only interesting if you do it with a bullet with enough mass to deliver energy levels comparable to a .223. A 31 grain bullet at 2300 FPS only delivers 364 ft-lbs of energy, which is comparable to a standard velocity 9mm.
We've done some testing in deer with 40 and 55 grain bullets at impact velocities near 2300 FPS, and we don't see anything much different from comparable energy levels from comparable handgun loads at similar penetration (.357 Sig and 10mm).
Crossing some velocity threshold doesn't help if you sacrifice bullet weight to do it. Getting to rifle-type velocities is only going to produce rifle-like incapacitation if you've also got rifle-like energy levels combined with the right penetration depth. In my mind, this begins at about 1000 ft-lbs of energy and 12" of penetration.
Two different bullets with comparable energy levels, penetration depths, and percentage of retained mass are likely to produce comparable incapacitation even if they differ greatly in velocity, mass, and/or diameter.
Michael Courtney
Borachon
Member
Agreed. If not more so than a .223.
I'm not sure that the new designs will make it past the monolith of legality however. The more effective...and energy efficient...that you make a pistol; the more likely you'll see legislation to curtail it's development and use...for civilians at any rate.
Exploding bullets, rocket propelled bullets, armor piercing...all of these offer interesting concepts for bullet design. But they are often limited by regulation.
Major Beer
Member
- Joined
- Aug 5, 2005
- Messages
- 82
this might have been the most informative post i have read in ages. tomorrow is gun season here in Ohio - i will be using my 50 cal muzzleloader. after reading the report on the 40 S&W performance on a deer shooting, i know full well of its potential of a self defense cartridge.
who knows, i may try hand gunning for deer eventually. for now, i'll stick with something with a scope that i can easily drop Bambi's parents at 100 yards.
thank you for all your posts Mr. Courtney - - facinating indeed.
who knows, i may try hand gunning for deer eventually. for now, i'll stick with something with a scope that i can easily drop Bambi's parents at 100 yards.
thank you for all your posts Mr. Courtney - - facinating indeed.
Michael Courtney
Member
Borachon said:
The regulatory side is an RKBA/legal discussion. This discussion is very interesting and relevant, but being a scientist (rather than a lawyer or politician), I feel my greater potential for contribution is on the scientific side in seeking to describe cause and effect relationships (how to increase incapacitation).
Of course, one recognizes that there may be constraints imposed by legalities, so one also endeavors to discover the most effective possibilities within a given set of constraints. However, considering the possibilities without constraints is an important step to maximizing the potential within the constraints.
Michael Courtney
How does your work differ from these works that have all been discredited?
Jeff
Michael Courtney
Member
Jeff White said:
These works focus on wounding. Our focus is on incapacitation. Wounding is a secondary consideration.
Our primary emphasis is on predicting and observing incapacitation effects without being bound to the unpresupposition that easily detectable wounding is always necessary for rapid incapacitation.
We have observed these incapacitation effects directly, and also confirmed the Strasbourg Goat tests which implanted a pressure sensor and to detect the pressure wave in the carotid artery. The Strasbourg data shows a very strong correlation between average incapacitation time and the pressure wave magnitude.
Michael Courtney
Have you got a link to the Strasbourg tests?
Jeff
Jeff
ghost squire
member
- Joined
- Aug 17, 2005
- Messages
- 339
I think when when the FBI Wound Ballistics people (Fackler among them) looked at the Strasbourg goat tests, within minutes they concluded that they were false.
Michael Courtney
Member
ghost squire said:
Yet to date, they are unable to provide conclusive evidence supporting this position.
The main case that the Strasbourg tests were fraudulent depends on their anonymity and the lack of supporting evidence (witnesses, documentation). However, reaching this conclusion "within minutes" based on anonymity and lack of supporting evidence is unsound.
In contrast, we have endeavored to test the hypothesis of fraud by using the results of the Strasbourg results of incapacitation times to make testable predictions of incapacitation in whitetail deer. Predictions based on Strasbourg are sufficiently accurate that this experiment has concluded with 90% certainty that the Strasbourg results represent genuine average incapacitation times.
In other words, if the Strasbourg tests were really fraudulent, they would show no correlation with a similar study in deer using substantially similar shot placement. The fact that the Strasbourg results can be used to accurately predict the results of a future experiment speak very strongly and directly to their validity.
Michael Courtney
ghost squire
member
- Joined
- Aug 17, 2005
- Messages
- 339
Allright, that seems fair, do you think you could link me to a full copy of these tests so I can see for myself what you are talking about?
Hmm, well, this is an interesting read, raising some interesting questions. If the TC is, in fact, just one of the observable effects of a larger "pressure wave", you feel that this pressure wave has positive effects on incapacitation times. Well, there is no doubt that a pressure wave of sufficient force can cause incapacitation through shock to the nervous system, but, AFAIK these types of pressure waves are usually not even produced by high velocity rifle rounds, usually only seen with the use of fast burning high explosives. So, my question is, if in fact the TC is just one effect of the overall "pressure wave", by what method does the "pressure wave" cause, or aid in, incapacitation? Is this a nervous system effect, or does this pressure wave lead to an increased rate of hemmorage, or something else?
James
James
Michael Courtney
Member
james481 said:
The TC is highly correlated with incapacitation time. It is less clear whether this indicates that the TC causes more rapid incapacitation, or merely that both the TC and rapid incapacitation are both caused by the pressure wave.
james481 said:
Good point, but there should be some advantage to applying the wave internally.
james481 said:
Our research to date has concentrated on becoming more certain of the causal relationship than on the specific physiological mechanisms.
For example, it only makes sense to investigate the specific biological mechanisms by which a dangerous chemical causes cancer once it has been determined with a high degree of certainty that a causal relationship exists.
By analogy, we have delayed investigating specific physiological mechanisms until after we concluded with a high degree of certainty that the pressure wave is an important causal agent of incapacitation. We believe that experiments like the Strasbourg goat tests that concentrate on incapacitation are important in identifying incapacitation without regard to specific physiological mechanisms.
james481 said:
Our ideas regarding specific physiological mechanisms are much less certain than our conclusion that the pressure wave can contribute significantly to incapacitation with handgun loads.
We tend to agree with the position put forward in:
Newgard, Ken, M.D.: "The Physiological Effects of Handgun Bullets: The Mechanisms of Wounding and Incapacitation." Wound Ballistics Review, 1(3): 12-17; 1992.
that incapacitaion from blood pressure drop due to internal bleeding will take around 5 seconds in a best-case scenario. We have also observed in deer that even the best shot placement with a 1.5" broadhead will take at least 5 seconds to produce incapacitation via blood-pressure drop. Therefore, we tend to believe that some effect other than bleeding is required to produce incapacitation in under 5 seconds.
However, using handgun loads that generate high pressure waves, we have observed instances of incapacitation in under 5 seconds without a direct hit to the CNS or supporting bone structure. Since we do not believe incapacitation this rapidly can be ascribed to bleeding, there must be another mechanism.
The Strasbourg observation using a pressure transducer in the carotid artery suggests the pressure wave impacting the brain may be important. We also believe that the blunt force trauma of the pressure wave on the spine may be able to cause temporary incapacitation to long enough for blood loss to take effect. We have observed cases where deer are shot with handgun bullets, drop immediately, and then regain mobility briefly until the loss of blood produces permanent incapacitation.
This leads us to consider the possibility that the pressure wave and blood loss work together in the more commonly observed immediate drop where the deer never regains mobility. In other words, the pressure wave produces temporary incapacitation for the 5-10 seconds needed for blood pressure drop to extend the incapacitation indefinitely.
In other observations, the deer doesn't become incapacitated for 2-3 seconds after bullet impact. Could the remote blunt force trauma on the spine or brain have this delayed effect? Could the incapacitation be resulting from a neurological effect shutting down some body systems?
We don't have definitive answers at this point, but we think we know what the questions are. Now that we have a high level of confidence that the pressure wave is an important causal agent in incapacitation, we are turning more attention toward considering specific physiological mechanisms.
Michael Courtney
ghost squire
member
- Joined
- Aug 17, 2005
- Messages
- 339
Emotional Fainting: An Involuntary Psycho-physiological Mechanism of Collapse
The unexplained magic of "energy transfer" is usually credited when a person immediately collapses unconscious after being shot in the torso with a handgun bullet. How else could someone be so quickly and decisively incapacitated, especially when the bullet didn't damage central nervous system organs, and the speed in which incapacitation took place precludes incapacitation by blood loss?
If you're a bullet company, you want people to believe that your product possesses unique powers to make bad guys instantly collapse. Energy transfer is popular belief, and you're going to tell your customers what they want to hear, despite the fact that there's no evidence whatsoever to support your claims or your customers' beliefs. If that's what the majority of your customers want to believe, then you're going to tell them that your bullets transfer more energy, and they do it faster and better than any other brand.
But if energy transfer isn't a mechanism of incapacitation, what is it that causes people to immediately collapse unconscious when other factors are ruled out?
In the last issue of Wound Ballistics Review, Fackler tackles this difficult question.¹ He identifies and describes a psycho-physiological mechanism of unconscious collapse called Emotional Fainting.
Fackler refers to Guyton2, and describes Emotional Fainting as "...[a] physiological mechanism, with an psychological cause, known as neurogenic shock — more specifically a type of neurogenic shock called 'Emotional Fainting'." Fackler explains:
"Strong emotions (such as fear) can cause widespread dilation of the body's blood vessels. These vessels have muscle fibers in their walls to allow them to constrict or dilate and thus vary blood flow as needed (in response to heat or cold, for example). The vessels are usually kept semi-constricted, but in Emotional Fainting, nerve impulses from the sympathetic nervous system can cause them to dilate completely. When this happens, the vascular capacity increases substantially and the blood available can no longer fill it. If the person is upright when this happens, gravity pulls the available blood into the legs and lower torso, starving the brain and causing the incapacitation."
Fackler continues:
"...the effects of Emotional Fainting, or some gradation of psychologically caused incapacitation (the gamut from surrender to Emotional Fainting), are either totally or partially responsible for much more of the observed reaction from bullet hits than is recognized. The practical result of this misinterpretation of the causes of reactions to being shot is overwhelming confounding effect on any attempt to compare efficacy of various bullets by observing, recording, and comparing the reactions of those hit."
Although Emotional Fainting appears to be a significant incapacitation mechanism, there's no evidence to suggest that any bullet characteristic (energy transfer, for example) triggers this reaction. While anecdotal reports of shootings seem to suggest that high-energy bullets are more effective in producing rapid incapacitation, these reports are tainted by the emotional bias of popular belief, which exaggerates stories that support the belief and suppresses those that do not.
Emotional Fainting is an unpredictable reaction and it is therefore unreliable. It is least likely to occur in people who are chemically intoxicated, psychotic, emotionally disturbed or acting with a single-minded determination to cause as much harm as possible before being stopped. It is probably most likely to occur in someone who is mentally unprepared to be shot or shot at.
Endnotes
Fackler, Martin L., M.D.: "Incapacitation Time." Wound Ballistics Review 4(1), Spring 1999; 4-8.
Guyton AC. Textbook of Medical Physiology, Eighth Ed., Philadelphia, PA. WB Saunders, 1992, p. 269.
http://www.firearmstactical.com/briefs29.htm
ghost squire
member
- Joined
- Aug 17, 2005
- Messages
- 339
Could it be the temporary cavity impacting the spine and knocking it unconcious? On a deer a broadside shot might let this happen fairly easily even with a handgun. On a human its unlikely because of all that stands between spine and chest, and the human is likely to be facing you.
Michael Courtney
Member
RyanM said:
The primary advantage of using deer is that we have a high level of certainty that observed incapacitation is involuntary and does not involve emotional fainting. In other words, it removes the "movie training" aspects of incapacitation that can be present in humans.
Michael Courtney
- Status
Similar threads
- Locked
