Smith & Wesson .500 Magnum

The goal of shooting someone boils down to one of two things- you either want to kill someone or you want them to stop what they are doing. Preferably before they can do it any more. Handguns are great at killing people; they are in fact the most common firearm used in murders in the United States. Nope, it’s not them thar evil assault rifles, it’s handguns. But stopping people? That’s a lot more complicated. It’s quite possible to kill someone without stopping them fast enough to do you any good.

First let’s define what it means to ‘stop’ someone. It means they immediately cease doing whatever it was that made you feel the need to shoot them. This can mean they surrender, run, faint dead away or even die more or less instantly. It can also mean that no matter how much they want to they are physically incapable of continuing. Basically there are two kinds of ‘stops-‘ the Psychological Stop and the Physiological Stop.

Technically if you point your gun at someone and they immediately surrender you have achieved a ‘Psychological Stop.’ For the purposes of this article, since it’s about stopping power, we’re going to assume a shot or shots were fired. So what produces a ‘Psychological Stop?’ Well, people don’t like being shot. They have been taught all of their lives that this is a very bad thing. So when they get shot Fight/Flight/Freeze reflex kicks in. In most cases Flight or Freeze wins, and either one of these constitutes a stop. The body also responds to trauma on an automatic level. Pretty often the brain responds to a gunshot injury by saying, ‘Right, we’re done.’ People that receive even minor gunshot injuries often find themselves sitting down with no idea how they got there. Odds are if you ever have to shoot someone they will either run like hell or be rendered ineffective by psychological shock.

The problem is Psychological Stops are unreliable. If the Fight reflex kicks in and you haven’t damaged something important you’re in real trouble- you shoot your assailant and he goes berserk. Statistically this result is a minority, but it happens. Other things can prevent a Psychological Stop as well- certain drugs like PCP, methamphetamine and alcohol can prevent it. Training and mental preparation on the part of your assailant can also play a significant role in preventing a Psychological Stop.

In short a Psychological Stop is likely, but not certain. With your life on the line you can hope for one but you have to train and focus on achieving a Physiological Stop. Which is unfortunate, because handguns suck at producing them. So how does one produce a Physiological Stop? Simply put by breaking something so important that their body cannot function without it. To accomplish this a bullet has to penetrate deeply enough to hit a vital structure, and has to be aimed well enough to actually do so. Vital Structures include the heart, the major veins, the brain and the spine. Of these only the brain and cervical spine are absolutely certain to produce an instant stop. People can and have been shot through the heart and continued to fight effectively for a surprisingly long time.

Handgun bullets are not, in the grand scheme of things, particularly powerful. As a rule they do not produce enough of a shockwave in bodily tissue to create permanent damage; a persons innards are amazingly elastic and surprisingly tough. High-powered rifle bullets can damage things inside the body that they don’t touch, but generally they are moving in excess of 2000 fps. This seems to be the threshold for what is inaccurately called Hydrostatic Shock. Properly speaking it is Hydrostatic Disruption- the bullet produces a shockwave in tissue severe enough to tear tissue that the bullet does not touch. Conventional handgun rounds don’t do this.This means that the only parts of the body that a handgun bullet will damage are the parts it actually touches. A larger diameter bullet will interact with more tissue, which up to a point increases their effectiveness. It doesn’t seem to matter whether the bullet starts out large or gets that way via expansion- the important point is that it damages more tissue.

But it’s not enough to damage more tissue; to insure a Physiological Stop the bullet has to hit the right tissue. Assuming the bullet has enough penetration to reach vital structures this is a function of the shooter.  Yep, that’s right- you are more important than the caliber or bullet type. If you don’t put the bullets where they need to go your assailant will not be forced to stop. No matter what gun, caliber or bullet type you are using you have to make sure it hits the right things. The easiest way to do this, as established by long experience, is to put multiple bullets in the middle of the attacker’s body. More bullets equals more gross damage and more chance of hitting a vital structure. The heart, the aorta and spine are all in the middle of the body. Any bullet you put through one of those structures will be better than any other bullet that doesn’t hit them. In that sense is doesn’t matter if it’s from a .25 ACP or a .44 magnum. Still, all things being equal more damage is better.

OK, but if a hit to the brain is the best way to insure a stop why not aim for that? Simple- it’s easier to hit the center of the body than the much smaller, more mobile head. Especially when under stress and acting as fast as humanly possible. More room for error with a center-mass aim point, and it moves around less.

If you have to use a handgun to defend your life or the lives of innocents your best bet is to use a service-caliber handgun and select good quality modern ammunition. Then you need to insure that it functions properly in your gun of choice, and train enough to reliably hit vital structures with those bullets. With proper ammunition selection which service-caliber you use is largely irrelevant; they all penetrate deeply enough and do enough damage to reliably produce a Physiological Stop with a well-placed bullet. This isn’t to say that smaller calibers are useless; far from it. With careful bullet selection any readily available handgun can produce an instant stop, but the smaller and less powerful a round is the less likely it is to be able to do so reliably.

The good news is that modern ammunition has come a long way, and there are a number of bullet designs in a variety of calibers that penetrate deeply enough and damage enough tissue to produce a Physiological Stop. The bad news is that whether or not they work is on you.