"Stopping Power" article

[Andrew Wiggin]

An article that I wrote was published in a minor blog.

There has been some discussion on “stopping power” of late so I think it’s time that we get a few things straight. First off, “stopping3598065314_7ccc33d168_b power” or “knockdown power” doesn’t exist. Velocity exists. Foot pounds exist. Momentum exists. Even tissue disruption can be quantified but there is no magical force called “stopping.”

The term “stopping power” is, at best, an awkward attempt to quantify the ability of a given cartridge or load to incapacitate an attacker. It may surprise you to know that Cracky McCrackerson, your friendly neighborhood crack head/rapist/burglar actually has no idea that your grandpappy’s 1911 is supposed to take a man’s arm off when it whizzes past. He doesn’t know that the stopping powertoothless suspender guy who seems nailed to that creaky stool at the gun store told you so. He doesn’t know that every gun rag ever written proclaims how singularly badass the .45 ACP is and how you have to buy a $3,000 1911 because ‘Merkah! You have to convince his body to stop trying to harm you. This is called “incapacitation.” What causes incapacitation, though?

The rest is here if you're interested.

 

[Glenn E. Meyer]

Thanks for the link to the article and snippet.

You made one mistake -. The 1911 not only takes off the arm of the target but it darn near takes off the arm of the shooter.

I'm a 5'8' FOG and was told this by two over 6 footers. One was in the Army (as you were) and told me that when he fired one it darn near took his arm off. Of course, he was a Lt. in the finance department. Another very large Minnesota moose hunter told me the same.

Unfortunately, I have shot about 100 or so 230 gr 45 ACP at a time in a match and seem to still have my arm. Thus I am confused.

 

[Andrew Wiggin]

It's too bad that girls can handle guns better than those big, macho men.

My wife:

 

[Sierra280]

I've never understood this whole 'stopping power' thing. When my better half said she wanted a carry, I suggested the Ruger SR22. Lightweight, easy to shoot and control, cheap and easy to get lots of practice with. The CCW instructor saw it and went off about 'stopping power'. He pointed out that 22lr rounds wouldn't have the stopping power to stop a charging crackhead, I asked for an example of someone being shot multiple times in the torso with a 22lr and still advancing; his response 'Oh, it happens! You better get something better' Needless to say, that was the end of that.

My logic was I would rather have her carry something she can shoot easily and accurately. In the example of the advancing crackhead, I'd much rather she shoots (and connects) with 10 22lr rounds, than fires and connects with 1 45acp round then misses with the next 6!! And no, a 22lr won't blow a huge hole in someone, but it will sure bounce around internally.

 

[Andrew Wiggin]

If there really were a reason that she couldn't shoot well with a 9mm, .40, .45, etc. then I would agree. A "real" service caliber would be far more effective. Dramatically more. With a CNS hit, almost anything will do, but that doesn't happen very often. Failing a CNS hit, you need to poke some pretty big holes to rapidly incapacitate. The difference between a 9mm and a .45 may not be all that dramatic, especially when using modern JHP, but the difference between .22lr and service pistol calibers is substantial.


That said, my biggest concern when someone considers carrying a .22lr is reliability. .22lr auto loaders are notoriously unreliable. A revolver can help somewhat but even .22lr ammunition is less reliable than center fire ammunition.

 

[Sierra280]

Good point, since stopping power is so important I'll just have her throw the Barrett over her shoulder when she goes out alone (with silver or black tips?) if FTF, she can just swing it like a baseball bat! Better yet, I'll send her with some SLAP rounds, if she is a victim of road rage, she will have the 'stopping power' she needs.

Seriously, though, we are not talking about Cape buffalo here. Human beings are frail, feel pain and fear. A 22lr carry that holds a bunch of ammo, is (assuming no FTF's, which have yet to happen) every bit as effective as a 9mm or 45acp for personal protection. If anyone has specific examples to the contrary (factual, not anecdotal) I'd love to hear them.

 

[uofudavid]

I understand what you are saying regarding 22lr, however the problem is reliability. This is true not only with the firearms that use 22lr but with the ammo as well. If the primer compound did not contact enough of the rim on the side the hammer strikes then there will be a FTF. This happens exponentially more than failure to fire with center fire ammunition.

IF the 22lr round fires then it might be an effective defensive round, but that is a really big IF and places even more pressure on precision shot placement in a high stress situation.

I see little difference in any of the common caliber handguns for stopping power from 38 through 45

 

[Sierra280]

I guess I've just been lucky, the only 22s I've had FTF was about half an old box of shorts someone gave me a few years ago. To stay in practice, at least twice a month (try to make it once a week, but things don't always work out) I go out to the range, set up some a23's and do the aggregate 4 position course (usually twice). I just use my lousy old marlin 60 and have yet to have a single FTF!

 

[Andrew Wiggin]

People who shoot even a small amount of .22lr are familiar with the unreliability of both the ammunition and the firearms in which they are chambered. This is a very well established fact and hardly worth discussion.

Your facetious post about carrying a .50 BMG notwithstanding, .22lr does cause dramatically less tissue damage than service pistol calibers. A S&W Shield or Sringfield XDS is hardly the size of an M82.

People who think that "the little lady" just cain't handle a center fire handgun are typically mistaken.

 

[RickB]

There was a "stopping power" article recently in American Hangunner magazine. It was most interesting because it appears to address "handguns don't have stopping power" by showing some statistics that prove 9mm is less effective than .380, and .45 ACP is no more effective than .32 auto. Carry a mouse gun, and carry confident!

 

[Andrew Wiggin]

Of course, those "conclusions" couldn't have anything to do with their desire to sell advertising....

 

[manta49]

There was a "stopping power" article recently in American Hangunner magazine. It was most interesting because it appears to address "handguns don't have stopping power" by showing some statistics that prove 9mm is less effective than .380, and .45 ACP is no more effective than .32 auto. Carry a mouse gun, and carry confident

I would like to see that article, and the stats. doesn't make sense to me.

 

[RickB]

You can read it online at americanhandgunner.com, Sep/Oct 2013 "digital" issue, page 52.

 

[Sierra280]

The point I was trying to make is that in the realm of everyday personal defense, stopping power is completely non-issue. Are there ANY stats or studies that support the need for a hand cannon as a personal protection weapon? Or, in such situations, is a 22lr every bit as effective?

All I hear is 'you need stopping power in a carry weapon' Can someone prove why?

No need to discuss possible reliability issues, it's already been covered. And ANY gun or caliber could have a misfire/hang fire/FTF, when it's needed. Also, this is focused on protection from other humans, clearly I would want a lot of power if an eland bull was mad at me.

BTW it's a M99, not an 82.

 

[Willie Lowman]

It was most interesting because it appears to address "handguns don't have stopping power" by showing some statistics that prove

Statistics that prove? Statistics that prove!

STATISTICS THAT PROVE?!?!?!?

BAH HAH HAH HA HA HAH HA HA HA!!!!

 

[Andrew Wiggin]

Sierra, if you read my article, you'll see some discussion of the mechanics of projectile wounding, which should in turn give you some understanding of why the .22lr cartridge is not particularly suitable for defense.

BTW, the M82 is also chambered in .50 BMG. Your post is still facetious and ridiculous. No one claimed or would claim, that someone should carry a gun chambered for .50 BMG. No one was even arguing that a .22 pistol was categorically a bad idea, just that there are some real, objective reasons to choose a more reliable, powerful weapon. Insisting that a female is incapable of carrying a more effective weapon is medieval thinking.

 

[Sierra280]

I read the entire article and I clearly understand that a 10mm will make a bigger hole in a BG than a 9mm or 22lr. But you are not understanding me; the ability to make a huge gaping wound doesn't make something more or less effective as a defensive carry. Or, at least, I've never heard a valid reason. Sure, a larger gun will incapacitate or kill probably more easily, but that's actually not the point; the point is stopping the BG from attacking or hurting you, and I see no reason (and haven't heard one yet) why a 22 can't serve the same purpose.

I also want to make it clear I NEVER claimed that woman can't handle big guns. My rationale for 22lr carry is that's it's small, lightweight, easy to handle, easy to shoot, cheap to practice with and for its size, holding 10rnds is great! When being fired upon, even the police have a pretty dismal hit percentage, I think more ammo in the gun is a good thing!! If I was going to carry it would also be a 22lr.

All I've been asking, is that; other than making a bigger hole, why is a bigger caliber carry necessary? (I already stated the reasons I'm a proponent of smaller carry weapons)


Wiggin: please stop jumping all over my posts, I was just looking for a reasonable explanation. And enough with the lesson on 50's, the 99 is really just the single shot (allegedly more accurate) version of the 82. Which BTW my woman has shot! It was to make a point. As even the article points out that really only rifles have 'stopping power.' So why carry a large heavy handgun?

 

[SIGSHR]

Let's discuss something less controversial-like whether we should shoot Low Number Springfields.
I'm of the "Hits hurt more than misses" school, and "Speed (and power) are fine, but Accuracy is Final." I recall reading years ago where Charlie Askins said that when he read the 1978 LEAA "Computer Man" report which said the 9MM had more stopping power than the 41 Magnum, he quit reading. I am not a hunter no do I play one on the Web, but one thing I have gleaned is that there is quite a range of deer cartridges and the choice often depends more on the skills-and physique-of the shooter than the power of the round.

 

[Frank Ettin]

I read the entire article and I clearly understand that a 10mm will make a bigger hole in a BG than a 9mm or 22lr. But you are not understanding me; the ability to make a huge gaping wound doesn't make something more or less effective as a defensive carry. Or, at least, I've never heard a valid reason. Sure, a larger gun will incapacitate or kill probably more easily, but that's actually not the point; the point is stopping the BG from attacking or hurting you, and I see no reason (and haven't heard one yet) why a 22 can't serve the same purpose....

Well let's consider how shooting someone will actually cause him to stop what he's doing.

• The goal is to stop the assailant.
  
  
• There are four ways in which shooting someone stops him:
  
  
  • psychological -- "I'm shot, it hurts, I don't want to get shot any more."
    
    
  • massive blood loss depriving the muscles and brain of oxygen and thus significantly impairing their ability to function
    
    
  • breaking major skeletal support structures
    
    
  • damaging the central nervous system.
  
  Depending on someone just giving up because he's been shot is iffy. Probably most fights are stopped that way, but some aren't; and there are no guarantees.
  
  Breaking major skeletal structures can quickly impair mobility. But if the assailant has a gun, he can still shoot. And it will take a reasonably powerful round to reliably penetrate and break a large bone, like the pelvis.
  
  Hits to the central nervous system are sure and quick, but the CNS presents a small and uncertain target. And sometimes significant penetration will be needed to reach it.
  
  The most common and sure physiological way in which shooting someone stops him is blood loss -- depriving the brain and muscles of oxygen and nutrients, thus impairing the ability of the brain and muscles to function. Blood loss is facilitated by (1) large holes causing tissue damage; (2) getting the holes in the right places to damage major blood vessels or blood bearing organs; and (3) adequate penetration to get those holes into the blood vessels and organs which are fairly deep in the body. The problem is that blood loss takes time. People have continued to fight effectively when gravely, even mortally, wounded. So things that can speed up blood loss, more holes, bigger holes, better placed holes, etc., help.
  
  So as a rule of thumb --
  
  
  • More holes are better than fewer holes.
    
    
  • Larger holes are better than smaller holes.
    
    
  • Holes in the right places are better than holes in the wrong places.
    
    
  • Holes that are deep enough are better than holes that aren't.
    
    
  • There are no magic bullets.
    
    
  • There are no guarantees.
  
  
• With regard to the issue of psychological stops see
  
  
  • this study by Greg Ellifritz. And take special notice of his data on failure to incapacitate rates:
    
    
    
    ​
    
    
    As Ellifritz notes in his discussion of his "failure to incapacitate" data (emphasis added):

    ...Take a look at two numbers: the percentage of people who did not stop (no matter how many rounds were fired into them) and the one-shot-stop percentage. The lower caliber rounds (.22, .25, .32) had a failure rate that was roughly double that of the higher caliber rounds. The one-shot-stop percentage (where I considered all hits, anywhere on the body) trended generally higher as the round gets more powerful. This tells us a couple of things...
    
    In a certain (fairly high) percentage of shootings, people stop their aggressive actions after being hit with one round regardless of caliber or shot placement. These people are likely NOT physically incapacitated by the bullet. They just don't want to be shot anymore and give up! Call it a psychological stop if you will. Any bullet or caliber combination will likely yield similar results in those cases. And fortunately for us, there are a lot of these "psychological stops" occurring. The problem we have is when we don't get a psychological stop. If our attacker fights through the pain and continues to victimize us, we might want a round that causes the most damage possible. In essence, we are relying on a "physical stop" rather than a "psychological" one. In order to physically force someone to stop their violent actions we need to either hit him in the Central Nervous System (brain or upper spine) or cause enough bleeding that he becomes unconscious. The more powerful rounds look to be better at doing this....

    
    
    1. There are two sets of data in the Ellifritz study: incapacitation and failure to incapacitate. They present some contradictions.
       
       
       • Considering the physiology of wounding, the data showing high incapacitation rates for light cartridges seems anomalous.
         
         
       • Furthermore, those same light cartridges which show high rates of incapacitation also show high rates of failures to incapacitate. In addition, heavier cartridges which show incapacitation rates comparable to the lighter cartridges nonetheless show lower failure to incapacitate rates.
         
         
       • And note that the failure to incapacitate rates of the 9mm Luger, .40 S&W, .45 ACP, and .44 Magnum were comparable to each other.
         
         
       • If the point of the exercise is to help choose cartridges best suited to self defense application, it would be helpful to resolve those contradictions.
         
         
       • A way to try to resolve those contradictions is to better understand the mechanism(s) by which someone who has been shot is caused to stop what he is doing.
       
       
    2. The two data sets and the apparent contradiction between them (and as Ellifritz wrote) thus strongly suggest that there are two mechanisms by which someone who has been shot will be caused to stop what he is doing.
       
       
       • One mechanism is psychological. This was alluded to by both Ellifritz and FBI agent and firearms instructor Urey Patrick. Sometimes the mere fact of being shot will cause someone to stop. When this is the stopping mechanism, the cartridge used really doesn't matter. One stops because his mind tells him to because he's been shot, not because of the amount of damage the wound has done to his body.
         
         
       • The other mechanism is physiological. If the body suffers sufficient damage, the person will be forced to stop what he is doing because he will be physiologically incapable of continuing. Heavier cartridges with large bullets making bigger holes are more likely to cause more damage to the body than lighter cartridges. Therefore, if the stopping mechanism is physiological, lighter cartridges are more likely to fail to incapacitate.
       
       
    3. And in looking at any population of persons who were shot and therefore stopped what they were doing, we could expect that some stopped for psychological reasons. We could also expect others would not be stopped psychologically and would not stop until they were forced to because their bodies became physiologically incapable of continuing.
       
       
    4. From that perspective, the failure to incapacitate data is probably more important. That essentially tells us that when Plan A (a psychological stop) fails, we must rely on Plan B (a physiological stop) to save our bacon; and a heavier cartridge would have a lower [Plan B] failure rate.
  
  
• Also see the FBI paper entitled "Handgun Wounding Factors and Effectiveness", by Urey W. Patrick. Agent Patrick, for example, notes on page 8:

  ...Psychological factors are probably the most important relative to achieving rapid incapacitation from a gunshot wound to the torso. Awareness of the injury..., fear of injury, fear of death, blood or pain; intimidation by the weapon or the act of being shot; or the simple desire to quit can all lead to rapid incapacitation even from minor wounds. However, psychological factors are also the primary cause of incapacitation failures.
  
  The individual may be unaware of the wound and thus have no stimuli to force a reaction. Strong will, survival instinct, or sheer emotion such as rage or hate can keep a grievously wounded individual fighting....

• And for some more insight into wound physiology and "stopping power":
  
  
  • Dr. V. J. M. DiMaio (DiMaio, V. J. M., M. D., Gunshot Wounds, Elsevier Science Publishing Company, 1987, pg. 42, as quoted in In Defense of Self and Others..., Patrick, Urey W. and Hall, John C., Carolina Academic Press, 2010, pg. 83):

    In the case of low velocity missles, e. g., pistol bullets, the bullet produces a direct path of destruction with very little lateral extension within the surrounding tissue. Only a small temporary cavity is produced. To cause significant injuries to a structure, a pistol bullet must strike that structure directly. The amount of kinetic energy lost in the tissue by a pistol bullet is insufficient to cause the remote injuries produced by a high-velocity rifle bullet.

    
    
  • And further in In Defense of Self and Others... (pp. 83-84, emphasis in original):

    The tissue disruption caused by a handgun bullet is limited to two mechanisms. The first or crush mechanism is the hole that the bullet makes passing through the tissue. The second or stretch mechanism is the temporary wound cavity formed by the tissue being driven outward in a radial direction away from the path of the bullet. Of the two, the crush mechanism is the only handgun wounding mechanism that damages tissue. To cause significant injuries to a structure within the body using a handgun, the bullet must penetrate the structure.

    
    
  • And further in In Defense of Self and Others... (pp. 95-96, emphasis in original):

    Kinetic energy does not wound. Temporary cavity does not wound. The much-discussed "shock" of bullet impact is a fable....The critical element in wounding effectiveness is penetration. The bullet must pass through the large blood-bearing organs and be of sufficient diameter to promote rapid bleeding....Given durable and reliable penetration, the only way to increase bullet effectiveness is to increase the severity of the wound by increasing the size of the hole made by the bullet....

  
  
• And sometimes a .357 Magnum doesn't work all that well. LAPD Officer Stacy Lim who was shot in the chest with a .357 Magnum and still ran down her attacker, returned fire, killed him, survived, and ultimately was able to return to duty. She was off duty and heading home after a softball game and a brief stop at the station to check her work assignment. According to the article I linked to:

  ... The bullet ravaged her upper body when it nicked the lower portion of her heart, damaged her liver, destroyed her spleen, and exited through the center of her back, still with enough energy to penetrate her vehicle door, where it was later found....

 

[iraiam]

I agree with the OP, although I usually state it differently, I generally say that "stopping power" is just softened language for "tissue damage". The more tissue or structural damage in the right place (center mass), the higher your probability of stopping someone.

I prefer heavier bullets for given calibers, 147 grain for 9mm,158 grain for 357, 230 grain for 45 auto.

If possible, I would shoot center mass in any instance where I was justified in pulling a weapon, I would not consider a leg shot or purposely trying to "wing" someone if I had center mass to target.