But, capacity!!!

Whenever someone (or I) say that quite often you are perfectly well armed with a snubby or a S&W Shield I hear – and I mean literally I hear, “Ah jes ain’t safe without ma Glock 17 and two 33 round sticks.  An ma back up knife, of course.  There’s whole gangs of evil fellas out there jes a’ preying on the likes of maself.”  (OK – I don’t usually hear the hillbilly accent here in New England – but the rest, absolutely.  (And apologies to actual hillbillies, who are usually pretty street-smart.))

Two words: Bell Curve.  Google it.  Yes, there are bad things that happen to good people at the extreme boundaries of probability.  These are the gunfights that make for entertaining, and often insightful, reading in the gun rags (including the largest of them all, the Net).  But they are, in stat-speak, several sigma out from the mean (they are wicked unlikely).

What’s far-and-away the likely bad event?  A car’s length and a couple shots.  Again, Google is your friend: look up the latest numbers about Tom Givens’ students.  (I lost track the last couple years after his students had been in over 60 gunfights – and won them all except for the couple who forfeited by not having a gun with them).

So yeah – a Shield or a snub, assuming you can get to it quickly and have a little skill.  Caveat: I’m talking United States, here-and-now, and civilians.

So what about the outliers – the extremely rare events in which you’d need that G17 and two 33-round back-up mags?    Yes, you could be the unfortunate victim of a whole hit squad from the Russian Mob – in which case you’ve probably made some bad choices.  Or you could be present at the next coordinated ISIS attack – but you’d be MUCH more likely to save you life by installing a 5-point seat belt in your car than gearing up daily for it*.  Really: you are thousands of times more likely to be average.  Also, just sayin’, no matter what gear you have you can’t win either of the two above events.  As John Farnam so insightfully  puts it, “You are far more likely to run out of time than rounds”.

There’s nothing wrong with being prepared, of course.  My carry gun is often one of the full-size models that I shoot the most.  But a lot of people take it to the extreme without any rational thought.  I mean, why not four 33-round sticks?  There is in fact a finite probability that you may need them.

I’ll leave you with this: You know you’re in for a confrontation tomorrow.  You don’t know how bad it’ll be – nothing indicates if it’ll be average (which is of course likely) or not (which of course isn’t).  You can send in a proxy in your place – but if he wins you live, if he loses you die.  Your choices: your strange ranger friend with that G17 and two 33-round mags, Wyatt Earp with his single-action S&W Model 3 revolver, or Jim Cirillo with a single snubby.


* But I know some civilian professionals who may well be there because of the responsibility they’ve taken on them selves – they are few in number.

4 thoughts on “But, capacity!!!

  1. It seems this has come up a lot lately. I have often used a couple of graphs of the far ends of the bell curve for illustration. If our goal is to minimize the probability of death by criminal, it is logical to start with things that provide the greatest reduction (like following Farnham’s Law). the probability can never reach 0, and the closer we get to 0 the higher the marginal opportunity cost. There is a point of diminishing returns.


    • Short answer: choosing between a 5 shot and a Glock 17 with two 33 round sticks is a false choice. They are mutually exclusive. Proper use of statistics show both are bad choices for civilians.

      Long answer:
      I believe the bell curve in deciding capacity is a flawed use of the graph. One must artificially bracket the curve in order to make sense of it. And we risk misusing statistics in order to decide something improperly.

      Examples: If I carry a gun my whole life but never need it, then the capacity needed was zero. I didn’t need a gun at all. If at some point I pulled my gun but didn’t fire, the capacity needed was zero. I could have carried a fake gun with the same effect. If I shoot my gun and it frightens the bad guy away how much capacity is needed to frighten a person away?

      If I need my gun and I shoot someone with it, what in my control influences the need for capacity? My ability to hit the target? That’s about it. That ability changes over time. If I get better over several years with training and practice I might have a higher percentage of my rounds hitting the target. Could that influence my choice? If so is my choice the same as your choice?

      The availability of a pain/psychological stop is not up to me, other than just shooting them again to hit a nerve center for more pain/chance of pain, shooting them somewhere else(CNS) or doing something else like retreating.

      When we properly bracket this graph it’s not a bell curve but an S curve. As the need for capacity presents itself it often is situational dependent where we have no control for the need. For the above reasons that tend to skew stats I believe a 5 shot is not a valid capacity. The 2 standard deviations on a proper graph would show that. It’s the intersection of that outside influence and choosing a 5 shot that has gotten people dead in the past. We know this from police stats. Many officers in the revolver days emptied the revolver. For them they did indeed run out of bullets before time. The same is true of some civilian gunfights. Of course saying that doesn’t mean one must run around with a 33 stick mag.

      As Tom has said in the past, you make your choices and take your chances.
      As a math major I say, choose wisely.
      As Taleb would say, we suck at math… LOL.


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