Knockdown Power??


Glockster20

Clinging to God and guns
I received this article in an email and thought it was very informative. Hope some of you will find it as informative as I did.

P1 Exclusive: The truth about handgun knockdown power

By Commander Jeffry L. Johnson
Long Beach Police Dept., Detective Division
Special contributor to PoliceOne

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There is undoubtedly no other myth more perpetuated and closely held (even now) by many law enforcement professionals than what I have previously referred to as the “Demonstrative Bullet Fallacy,” or in plainer terms, the idea that any handgun of any caliber has “knockdown power,” in that the sheer size and force of the bullet can knock a person down. Closely related is the myth that bullet size — rather than shot placement — can determine or ensure a “one shot stop.” Both are inaccurate, unscientific, and dangerous, and have no place in the training of law enforcement professionals.

Not that any of this is new information. This fact has been generally known for about six hundred years or so. Notable intellects such as DaVinci, Galileo, Newton, Francis Bacon, and Leonard Euler all studied physics and ballistics, as did many others. It was Newton’s research that led Benjamin Robbins to invent the ballistic pendulum in 1740 (the first device to measure bullet velocity).

There is no mystery here — the truth has been documented time and again. So how is it that we still don’t get it? One word: Hollywood.

Ever since Dirty Harry came along with his .44 Magnum hand-cannon, when someone gets shot in the movies or on TV (and don’t forget video games) two things happen: 1) the victim is thrown back convulsively, through windows, off balconies, etc. and 2) there will immediately emerge a geyser of blood spewing forth from the wound, leaving no doubt that this person has been shot, and pinpointing exactly where the bullet has struck.

Many firearm and shooting magazines picked up on the idea as well, discussing and propagating the pseudo-scientific idea of handgun “knockdown power” and “one shot stopping power.”

The Truth
The Federal Bureau of Investigation Firearms Training Unit published a concise yet insightful report that speaks directly to this issue of firearm wounding ballistics and the misconceptions that have surrounded this area.

These so called [knockdown power] studies are further promoted as being somehow better and more valid than the work being done by trained researchers, surgeons and forensic labs. They disparage laboratory stuff, claiming that the “street” is the real laboratory and their collection of results from the street is the real measure of caliber effectiveness, as interpreted by them, of course. Yet their data from the street is collected haphazardly, lacking scientific method and controls, with no noticeable attempt to verify the less than reliable accounts of the participants with actual investigative or forensic reports. Cases are subjectively selected (how many are not included because they do not fit the assumptions made?). The numbers of cases cited are statistically meaningless, and the underlying assumptions upon which the collection of information and its interpretation are based are themselves based on myths such as knockdown power, energy transfer, hydrostatic shock, or the temporary cavity methodology of flawed work such as RII. (1)

The truth is, the whole idea of handgun knockdown power is a myth. It simply doesn’t work that way. The FBI report further clarifies:

A bullet simply cannot knock a man down. If it had the energy to do so, then equal energy would be applied against the shooter and he too would be knocked down. This is simple physics, and has been known for hundreds of years. The amount of energy deposited in the body by a bullet is approximately equivalent to being hit with a baseball. Tissue damage is the only physical link to incapacitation within the desired time frame, i.e., instantaneously. (2)

The report cites previous studies that have calculated bullet velocities and impact power, concluding that the “stopping power” of a 9mm bullet at muzzle velocity is equal to a one-pound weight being dropped from the height of six feet. A .45 ACP (45 auto) bullet impact would equal that same object dropped from 11.4 feet. That is a far cry from what Hollywood would have us believe, and actually flies in the face of what even many in law enforcement have come to mistakenly believe.

The FBI report also emphasizes that unless the bullet destroys or damages the central nervous system (i.e., brain or upper spinal cord), incapacitation of the subject can take a long time, seemingly longer if one is engaged in a firefight.

Failing a hit to the central nervous system, massive bleeding from holes in the heart or major blood vessels of the torso, causing circulatory collapse is the only other way to force incapacitation upon an adversary, and this takes time. For example, there is sufficient oxygen within the brain to support full, voluntary action for 10-15 seconds after the heart has been destroyed. (3)

More often than not, an officer firing at a suspect will not immediately know if he or she has even struck the target. The physics are such that the body will rarely involuntarily move or jerk, and usually there is no noticeable spewing of blood or surface tearing of tissue. Often there is no blood whatsoever. (4) That is why military surgeons and emergency room physicians take great time and pains to carefully examine gunshot victims for any additional small holes. Often that is the only indication the person has been shot.

Personal Experience
But let’s be real here. I can cite numerous additional academic and scientific sources that support this article, but I know how cops think. We’re not always the most trustful of academics, especially when it comes to our street survival. So let me add my own personal experience to the data. Please allow me to go beyond the cold facts and share with you why I know what I’m telling you is the truth.

In the mid-1980s I was involved in my first shooting as a police officer. But to give the story context, I must go back to 1982 when I graduated from the Long Beach Police Academy. The first thing I was told by experienced training officers I trusted and looked up to, was to “get rid of that pea-shooter 38 they issued you and buy a real gun with some knockdown power!” Although we were issued .38 caliber revolvers, we were authorized to carry a number of different caliber weapons on duty, the largest of which was the 45 Long Colt.


The .45 Long Colt round next to the diminutive 9 millimeter.

Imagine my surprise when I was confronted by a suspect armed with a shotgun in a dark alley and my Long Colt didn’t live up to its billing. I fired five rounds at the suspect. It wasn’t until I fired my last shot — intentionally aimed at his head — that he went down. I can’t begin to relate to you the surprise and horror I felt when there was absolutely no outward indication I was hitting my target. It was the kind of situation cops have nightmares about.

What actually happened? I fired five rounds at a distance of about twelve feet. The first one missed completely. The second struck his upper leg and broke his femur. The third struck him in the shoulder/chest. The fourth round hit him dead center—in the heart. And of course, the fifth was a headshot. Three of the five rounds created fatal wounds, though only one had immediate results.

Needless to say, I was pretty shaken by the whole thing. Not by the morality of what I’d done; the suspect had already fired at a bystander and taken a hostage earlier. He was also high on PCP. That wasn’t my inner struggle. What shook me was how unprepared I felt; how totally off guard I was taken by what occurred. No one ever told me it would be like that. The reality was contrary to everything I thought I knew about deadly force.

That experience more than any research or study is the reason is why I am writing this article. Police officers risk getting into shootings every day; we need to know the dynamics of how a shooting incident may unfold. It will affect our equipment, tactics, and most important, our mindset. We need to know that rarely will one shot incapacitate an assailant. We further need to be able to explain this when our fellow officers are involved in shootings where multiple shots are fired. The public honestly believes it’s like the movies. Why would we ever need to fire twenty or thirty rounds to subdue an armed suspect? Problem is we can’t teach it or explain it until we understand it ourselves. (5)


Footnotes:
1. Patrick, Urey W., Federal Bureau of Investigation, Firearms Training Unit, “Handgun Wounding Factors and Effectiveness,” p.13. (1989).
2. Ibid., p.9.
3. Ibid., p. 8.
4. Newgard, Ken, MD, “The Physiological Effects of Handgun Bullets: The Mechanisms of Wounding and Incapacitation” (1992).
5. For you visual learners still unconvinced, I highly recommend viewing the Discovery Channel MythBusters segment, “Blown Away,” (Brown Note Episode, Second Season), where the knockdown power myth is visually and scientifically debunked once and for all.
 

I tend to believe that handguns in general don't have "knock down" power, although a S&W model 500 .50 cal pistol may come close. What really should be discussed is man stopping power. The Hatcher scale of relative stopping power does a good job of rating various calibers.
 
G

gpbarth

Guest
One of my favorite shows is "Mythbusters," and they did a show not too long ago precisely about the "knock-down" power of bullets. The closest they came to one was with a 12GA shotgun with a solid slug, which DID move the target slightly, and blew out most of the back (probably taking the spine had it been a human being). And they fired everything from a .38 to a .45 to a .357 and a .44 Mag., along with several rifles (a 30.06, a .223 and a 7.65).

It's all Hollywood. And I have a friend in LE who shot a perp 6 times before he stopped - he was high on crack, and probably wasn't even feeling the rounds until his heart stopped. Drugs will keep an otherwise dead man fighting. And don't know if you remember in the news awhile back, but a perp here in Central Fla., after fleeing from the police and shooting a cop and his dog, was gunned down by several officers firing too many rounds to count. When asked why the cops stopped shooting, the chief said, "they ran out of ammo."
 

HK4U

New member
Good article. That is why I prefer a lot of smaller rounds instead of a few larger ones.
 
Shades of Rodney King...


Keep in mind that if the officers feel "threatened", as in the guy has been shot several times and continues to advance on them, they will keep shooting. I don't think that "they ran out of ammo" was the best response, but it probably summed up what happened. What may have been ommitted was the part about the BG kept advancing on the officers.



gf
 

tattedupboy

Thank God I'm alive!
I believe in the idea of knock down power to the extent that shot placement and the type of round used (ie., a hollow point or FMJ) are factors. A hit to the central nervous system by a hollow point round will almost certainly achieve this effect. This is why it is important that anyone making the decision to carry first learn how to shoot. A person who has never shot a gun in their entire lives who decides to stick a .500 Smith and Wesson in their waistband loaded with FMJs is almost certainly a recipe for disaster. I would trust a seasoned shooter carrying a 9mm loaded with hollow points any day.
 

wuzfuz

New member
Knockdown Power

I was lucky enough to have had a mentor in my early days witht he sheriff's department who knew a lot more about guns than most people do. One of the first thing he taught me was to ignore the Hatcher and Thompson graphs of stopping power. I have seen handgun ammo do a lot of really strange things, and I will shoot and keep shooting until the threat no longer exists. I was sent of a shooting call one night, and found a car with four young men in it. They had been passing around a 9mm pistol when it went off. The bullet hit the driver just above the eyebrow line and almost dead center, then took out the driver's window. The guy went to work the next morning with two black eyes and a bandaid over the abrasion on his forehead. The bullet had actually ricocheted off his forehead. Usually, that would have been a fatal shot, but it didn't happen this time. Just a little research reveals stories about bullets being deflected by sunglasses, hat badges, a cigarette lighter and so forth. When our deputies fired on the van the Tyson gang tried running our roadblock in, our .38 rounds dimpled the body metal. Really disheartening, "Halt, or I'll scratch your paint!" Fire center of mass, and keep firing until the threat is gone. The only answer, regardless of your ammo.
 
I was lucky enough to have had a mentor in my early days witht he sheriff's department who knew a lot more about guns than most people do. One of the first thing he taught me was to ignore the Hatcher and Thompson graphs of stopping power. I have seen handgun ammo do a lot of really strange things, and I will shoot and keep shooting until the threat no longer exists. I was sent of a shooting call one night, and found a car with four young men in it. They had been passing around a 9mm pistol when it went off. The bullet hit the driver just above the eyebrow line and almost dead center, then took out the driver's window. The guy went to work the next morning with two black eyes and a bandaid over the abrasion on his forehead. The bullet had actually ricocheted off his forehead. Usually, that would have been a fatal shot, but it didn't happen this time. Just a little research reveals stories about bullets being deflected by sunglasses, hat badges, a cigarette lighter and so forth. When our deputies fired on the van the Tyson gang tried running our roadblock in, our .38 rounds dimpled the body metal. Really disheartening, "Halt, or I'll scratch your paint!" Fire center of mass, and keep firing until the threat is gone. The only answer, regardless of your ammo.


Very poor tactical planning to set up a roadblock and not have anything more powerful than your standard sidearm. :nono: If a known threat exists (hence the "roadblock"), then it wold be SOP to have a shotgun, patrol rifle, or both ready to "stop the threat", knowing that a .38 revolver is not very effective against a perp determined to run the roadblock. :eek:

I've seen .223 rounds deflect off of the windshield of an oncoming vehicle, but the 12ga 00 buckshot or slugs have always punched through.


gf
 

HK4U

New member
I was lucky enough to have had a mentor in my early days witht he sheriff's department who knew a lot more about guns than most people do. One of the first thing he taught me was to ignore the Hatcher and Thompson graphs of stopping power. I have seen handgun ammo do a lot of really strange things, and I will shoot and keep shooting until the threat no longer exists. I was sent of a shooting call one night, and found a car with four young men in it. They had been passing around a 9mm pistol when it went off. The bullet hit the driver just above the eyebrow line and almost dead center, then took out the driver's window. The guy went to work the next morning with two black eyes and a bandaid over the abrasion on his forehead. The bullet had actually ricocheted off his forehead. Usually, that would have been a fatal shot, but it didn't happen this time. Just a little research reveals stories about bullets being deflected by sunglasses, hat badges, a cigarette lighter and so forth. When our deputies fired on the van the Tyson gang tried running our roadblock in, our .38 rounds dimpled the body metal. Really disheartening, "Halt, or I'll scratch your paint!" Fire center of mass, and keep firing until the threat is gone. The only answer, regardless of your ammo.



Fire center of mass, and keep firing until the threat is gone.
I think it is Gabe Saures that teaches, the concept "Shoot em to the ground". On that note I also suggest in training to mix the number of shots you fire each time. Don't get in the habit of shooting one and stopping or two and stopping or three. Change it around. Mix it up. If you train to shoot x number everytime you might just do that in a life or death cituation out of habit rather than shooting until the threat is no more.
 
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gpbarth

Guest
Very poor tactical planning to set up a roadblock and not have anything more powerful than your standard sidearm. :nono: If a known threat exists (hence the "roadblock"), then it wold be SOP to have a shotgun, patrol rifle, or both ready to "stop the threat", knowing that a .38 revolver is not very effective against a perp determined to run the roadblock. :eek:

I've seen .223 rounds deflect off of the windshield of an oncoming vehicle, but the 12ga 00 buckshot or slugs have always punched through.


gf

And that's why the ambush of Bonnie and Clyde used Browning automatic rifles (BARs). No dimpling of the paint there, more like Swiss cheese. Of course, B & C also had a Browning or two, so the LE guys were just leveling the playing field. And that's why I wondered why the cops were so ill-equipped in that LA bank robbery shoot-out a few years ago. I mean, they had to go to gun shops to get the necessary firepower. And one of the BGs ended up committing suicide before they got him.
 

ascendmfg

New member
Excellent

This is an excellent example of real education being used in the correct way.

Thank you for a great post.

IMHO this should be a sticky, and refered to when the caliber wars erupt again at some point in the future.

Practice, practice, practice................and then practice more.

Shot placement is the key..................NOT pray and spray!

Thanks again for a very informative post
 

festus

God Bless Our Troops!!!
look up stopping power

stopping power and Dr Fackler are very good resources for handgun capability
 

tattedupboy

Thank God I'm alive!
I just wish that more mention had been made of ammo choice, ie., HPs vs. FMJs. Otherwise, very insightful.
 

capo2186

New member
Awesome Article!

Very good article. Like many of you have said and I will continue to say, it’s better to have a well placed shot with a lower cal than a wild shot with a larger cal. I always tell people to carry what they are comfortable shooting. When it comes time for me to choose a carry weapon, it’s going to be whatever I feel I can shoot best and feel most comfortable shooting.
 
I was lucky enough to have had a mentor in my early days witht he sheriff's department who knew a lot more about guns than most people do. One of the first thing he taught me was to ignore the Hatcher and Thompson graphs of stopping power.

Wuzfuz, many authorities believe in the hatcher scale. It may have existed for quite some time but is still usable today. Even Jeff Cooper was a big fan of the scale. Nothing is perfect but the Hatcher Scale is very useful in determining man-stopping power.

Some Thoughts On Jeff Cooper and the Modern School
 

tattedupboy

Thank God I'm alive!
Very good article. Like many of you have said and I will continue to say, it’s better to have a well placed shot with a lower cal than a wild shot with a larger cal. I always tell people to carry what they are comfortable shooting. When it comes time for me to choose a carry weapon, it’s going to be whatever I feel I can shoot best and feel most comfortable shooting.

AND, as I keep saying, it's better to do all of this with HPs than with FMJs. Being able to hit the right spot won't mean a hill of beans if the bullet passes right through the target.
 

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