The Myth of Knockdown Power

Discussion in 'General Handgun Discussion' started by KalashnikovJosh, Jun 9, 2010.

  1. KalashnikovJosh

    KalashnikovJosh New Member

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    The truth about handgun knockdown power
    11/19/2008

    P1 Exclusive: The truth about handgun knockdown power
    By Commander Jeffry L. Johnson
    Long Beach Police Dept., Detective Division
    Special contributor to PoliceOne

    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.
     
  2. Davyboy

    Davyboy New Member

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    Interesting stuff Josh
     

  3. BigO01

    BigO01 New Member

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    Yes indeed this Tall Tale seems to have been around longer than even the age of electronics started .

    I remember when in my 20's I ran into an old friend from high school at a bar and while catching up and drinking talking guns and it turns he had dissapeared into the Army for 4 years which came with many interesting stories the best of which was what his DI had told him regarding the 45 while in Basic training .

    I couldn't help but almost falling off of my Bar Stool when he said that this clown had told the class as they were about to get to shoot the 1911 and that being hit with a bullet from it was like getting hit with a Brick traveling at 90 MPH !!

    When I finally caught my breath and could talk I had to tell him that between a Brick going that fast and a little 45 bullet the brick would win hands down in the stopping power department but the 45 had much better Killing power .

    I then had to sit and try to make him understand the difference betweeen the two .
     
  4. Dillinger

    Dillinger New Member

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    This issue has been beat to death in many threads.

    I always come back to the training I received at the hands of Rob Pincus. Combat Focus. Your attention is fixed on one threat, you fire your weapon until that threat is eliminated, then you move on to the next threat.

    Now, when you are slinging .45ACP rounds as fast as you can pull the trigger, those threats do go away faster than if you were shooting the same number of bullets from say a .22LR

    That doesn't mean the .22LR can not be effective in the same situation, it will just take more shots to complete the process.

    Either way, with Combat Focus, you stay trained on that one target until the threat is eliminated. If it takes 1 shot, great, but if not, you are trained to continue shooting until you have achieved that conclusion.

    JD
     
  5. canebrake

    canebrake New Member

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    Drop the one with the shotgun first.
     
  6. ScottA

    ScottA FAA licensed bugsmasher Lifetime Supporter

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    So the moral of the story is... go for the head-shot?
     
  7. Dillinger

    Dillinger New Member

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    I hope your kidding. :confused:

    I would say the moral is don't get stingy with your bullets in a self-defense shooting situation. :)
     
  8. NGIB

    NGIB New Member

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    Look, everyone knows that if you get hit with a .45 you'll immediately be picked up and thrown 32 feet through the air. If it's a center mass shot, the 32 foot flight will include a few back flips as well. One caveat is that the .45 round must come from a quality 1911.

    This must be true as I saw it on TV...
     
  9. ScottA

    ScottA FAA licensed bugsmasher Lifetime Supporter

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    That's what the question mark is for. Doesn't make sense to me either.
     
  10. KalashnikovJosh

    KalashnikovJosh New Member

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    It makes perfect sense.Hit the guy with what you got where it hurts as much as you need to till he drops.Dont rely on 'one shot stops' or the 'massive knockdown power' of caliber X,or the 'super hydrostatic shock' of a $2 dollar handgun bullet.(Dillinger I'd be pretty stingy with a magazine or a cylinder full of $2 bullets,wouldn't you?)

    Dont choose your weapon or your ammo believing it will do the job for you.Choose it because it gives you that 'special' feeling deep down inside.:D

    Choose it for your ability to use it well and your comfort with the weapon.

    That being said-there is no point to the 'caliber wars'.
    Were better off discussing how to train to hit the vitals.

    While all are not 'equal',if you make a good decision and choose a gun/ammo combo that works well for you and gets the job done,and you learn to use that weapon well-it doesnt matter if you like a .45 or a 9x19.

    Both of them have plenty of ballistic energy and will do the job of putting down a man sized target by hitting his vitals.
     
    Last edited: Jun 10, 2010
  11. spittinfire

    spittinfire New Member Supporter

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    I shot a deer at 75 yards with a 30-06 and it knocked him down. Rolled him over actually and he didn't get back up.
     
  12. Dillinger

    Dillinger New Member

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    No offense bro, but with thinking like that, I don't want you ANYWHERE near me when the zombies start walking the Earth.

    I don't care if I dump $127 of lead into a bad guy. Hell, I don't care if I have to resort to one mag/one kill of the GOOD stuff.

    If I go home and he DOESN'T - that is all the justification that I need.

    Combat Focus by Rob Pincus. You focus on one target and you shoot it until that threat is eliminated. Period. End of conflict.

    JD
     
  13. KalashnikovJosh

    KalashnikovJosh New Member

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    No offense taken-I dont carry 2 dollar bullets in my handgun.;)

    Wont have any trouble unloading one of my 20 round HP mags fulla hot CIP spec ball into a zombie.

    Handguns are handguns and rifles are rifles.I've heard stories of German 8mm Mauser knocking men down too.But I've seen footage of the vaunted .45acp being used by a state trooper to deal with what looked like a 125lbs transient druggie who came at him with a knife at a rest stop-the guy still had enough fight in him to keep trying that crap with a bullet from that troopers' .45 in his pelvic region,delivered at point blank range.

    Handguns are poor performers when compared to rifles or shotguns.

    I guess its good for me that 00 buck shells can be had for around a dollar a shell.

    I wouldn't have any problem making someone 5 dollars richer with their own lead deposits if it comes down to it.

    (can I be on your team now dillinger?:p)
     
    Last edited: Jun 11, 2010
  14. spittinfire

    spittinfire New Member Supporter

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    Are you saying my 45 won't knock a man down?!?!?! Kidding bro, I'm on your side. I'm sorry but I get a little tired of this debate because anyone with any sense knows that a pistol is only good for fighting your way back to a long gun. The only reason pistol power is a concern is because people want to carry them places one may not be able to hide a long gun.
     
  15. Jpyle

    Jpyle New Member

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    Bullets don't knock people down...they fall down when they're dead.
     
  16. KalashnikovJosh

    KalashnikovJosh New Member

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    No,no,no-no 'sides'.LOL.:)

    The whole caliber war thing is crazy.:rolleyes:

    9x19 aint gonna knock a man down either-but I wonder if 7.62x54r heavy ball from my M44 Mosin-Nagant would?

    I just wanted to go in depth to help un-confuse (total non-word there,eh?) the original poster asking about handgun 'stopping power'.

    Theres nothing to it really-handguns will work if you hit someone where it counts.They also seem to work better when you hit someone multiple times in a fast succession of shots.

    I read somewhere that after the first one or two shots,if the person shot isnt down,they can then take more punishment like it isnt even happening.

    So what Dillinger is saying about his preferred method is pretty much correct-hit them hard and fast till they drop.

    And no,I'm not advocating trying for the head shot every time,unless they're zombies for real......but I'd say that if you dumped 4 .32,.380,9x18,.38spcl,9x19,.40,.45,10mm or even 4 magnums or whatever into someones upper chest as fast as you could they're not gonna be much of a problem for you any longer.

    You shouldn't worry so much about caliber and 'stopping power' as much as you should worry about learning how to use what you've got to its best advantage....if you have faith in your weapon and can use it well,and know for a fact the projectiles will penetrate and do their job as much as you can do your job and put them where they belong,then your good to go.
     
    Last edited: Jun 11, 2010
  17. DrumJunkie

    DrumJunkie New Member

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    When it comes down to it all pistols are an exorcise in compromise. You want full on "stopping power" pack a rifle around. I really think the terms like stopping power come form ammo makers.
     
  18. KalashnikovJosh

    KalashnikovJosh New Member

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  19. DrumJunkie

    DrumJunkie New Member

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    The reloads I practice with are much like those. While I don't carry what I reload I could if need be and would not worry much about their performance. I also do not download being I think it's a little silly. I like to practice with similar loads that I'll carry. I feel download ammo just does not hep you when you are thinking on the back of your head that the recoil is going ot be more with SD loads. I've used a few different types of Fiocchi rounds. I really like how they work in tests I've done around here to see how they act on impact.:)