Stopping Power of various Calibers

[BucksCountyBob]

I don't know if this has been posted before, but I've seen many arguments break out here on the merits of various rounds in terms of stopping power, with many people saying that the .45 ACP is the ultimate bad guy stopper. Here's a link to a study a friend of mine sent me this morning that I thought was interesting. I'd paste the whole thing here, but it's an awful lot of data, so best to link to it, I think.

Feel free to draw your own conclusions from the data.

Link to Stopping Power study.

Regards,

BCB

[paplinker22]

Everyone is of course entitled to their opinion....hopefully this thread doesn't turn into a flame war.

"Stopping power" is a myth. The whole idea of being "knocked over" when a projectile impacts is a movie thing. My limited knowledge of physics tells me this: A projectile cannot hit with any more force than its mass times acceleration. It is physically impossible for a typical caliber to forcibly push a person off their feet.

Many people who are shot fall down which is a psychological response which appears as a person being knocked down.

To answer your question on caliber selection:
1. The only thing that matters is hits on target. Shoot the biggest caliber you can reliably shoot and conceal
2. Relatively speaking, pistol calibers suck. Which is to say, they're all the same in that regard. Ideally, you use a pistol to fight your way to a rifle. There is no national database or anything but the majority of people shot with pistols survive.
3. Anytime someone says X caliber is weak and lacks knock down power ask them if they're willing to test their theory. The point is, I don't think anyone wants to be shot at all regardless of the caliber. They're all potentially lethal.

Bill

[QuackXP]

I don't know if this has been posted before, but I've seen many arguments break out here on the merits of various rounds in terms of stopping power, with many people saying that the .45 ACP is the ultimate bad guy stopper. Here's a link to a study a friend of mine sent me this morning that I thought was interesting. I'd paste the whole thing here, but it's an awful lot of data, so best to link to it, I think.

Feel free to draw your own conclusions from the data.

Link to Stopping Power study.

Regards,

BCB

I don't have the time now to put that all in a spread sheet and start looking for min, max and average figures. But this is my observation

Lets take out .22 .25 and .32. They are not popular calibers for modern defensive firearms. Same with the .44MAG.

So that leaves us with .380 .38 .357 9mm .40 S&W and .45 ACP.

They all clock in a one shot stop at about %30-45. It looks like the average shots to incapacitation are around 2.0 and actual incapacitation around %50.

This leads me to believe that there is no one distinctive choice, as far as stopping power. This does not mean there is a right choice for YOU. What is the biggest firearm you will carry day in and day out? Is that a subcompact .380 well that .380 will be way more effective than the .45 that you left at home.

The data also seems to show that landing more than one shot is better. So those extra rounds you will get out of 9mm or .40 over .45 may come into play.

[Philiberty]

I'm been a firm believer in point # 2 above. Handguns suck, the only reason they are used for self defense is they are portable and concealable. The last set of data I saw indicated about 6 out of 7 people shot with a handgun survive.

[QuackXP]

I'm been a firm believer in point # 2 above. Handguns suck, the only reason they are used for self defense is they are portable and concealable. The last set of data I saw indicated about 6 out of 7 people shot with a handgun survive.

From: FBI Handgun Wounding Factors and Effectiveness

A review of law enforcement shootings clearly suggests that regardless of the number of rounds fired in a shooting, most of the time only one or two solid torso hits on the adversary can be expected. This expectation is realistic because of the nature of shooting incidents and the extreme difficulty of shooting a handgun with precision under such dire conditions. The probability of multiple hits with a handgun is not high. Experienced officers implicitly recognize that fact, and when potential violence is reasonably anticipated, their preparations are characterized by obtaining as many shoulder weapons as possible. Since most shootings are not anticipated, the officer involved cannot be prepared in advance with heavier armament. As a corollary tactical principle, no law enforcement officer should ever plan to meet an expected attack armed only with a handgun.

The handgun is the primary weapon for defense against unexpected attack. Nevertheless, a majority of shootings occur in manners and circumstances in which the officer either does not have any other weapon available, or cannot get to it. The handgun must be relied upon, and must prevail. Given the idea that one or two torso hits can be reasonably expected in a handgun shooting incident, the ammunition used must maximize the likelihood of immediate incapacitation.

http://www.firearmstactical.com/pdf/fbi-hwfe.pdf

I personally carry and keep a handgun in the nightstand to have convenient and immediate access. In a bump in the night scenario or a breakdown in social order scenario a rifle is only steps away.

[Philiberty]

I also think the study is misleading. It doesn't take demographics into account, such as the type of gun people are more likely to use. IE gangbangers who commit most of the gun crimes and are more likely to use a 9mm or 40 s&w which are obviously more powerful than a little 32 auto, but the study shows they have less % of incapacitation. 32 might also have higher rates of incapacitation because you will often see average street thugs spraying rounds across the block with their 9 but a small gun like 32 is more likely to be used at closer ranges. It's a nice try but in the end you need to be shooting whatever gun feels the best and you personally are more accurate with.

[ALS]

As I was told by a U.S.M.C. Scout Sniper instructor, A hand gun is for buying you time to get to the trunk where the real weapons are kept.

[Lobo41]

I've seen 3 people shot this year. #1 One 9mm to the back of head-dead. #2 One 9mm just inside the shoulder hit the clavicle ricochet down through the heart and into the stomach- dead. #3 One 9mm to the hip- survived and went and committed #1 as retaliation. This tells me it's more about shot placement. Go center mass and don't stop till they stop.

[QuackXP]

I've seen 3 people shot this year. #1 One 9mm to the back of head-dead. #2 One 9mm just inside the shoulder hit the clavicle ricochet down through the heart and into the stomach- dead. #3 One 9mm to the hip- survived and went and committed #1 as retaliation. This tells me it's more about shot placement. Go center mass and don't stop till they stop.

Was #1 in a gunfight or executed? If nobody is fighting back and you can take all the time in the world even a .22 should be effective.

[animalmother85]

Speed(increase in speed = increase in energy), energy transfer and bullet design are the biggest factors in pistol ammunition and they all tie in together...sort of.

Speed kills, plain and simple. A 70gr 9mm bullet at 1600fps carrier more energy(398ft/lb) than a 174gr 45cal bullet at 850fps (273 ft/lb), both being of the same design, just different diameter (.098" difference).
By minimizing pass-through by expansion, you are able to get more energy into the target.

Bullet design will help slow the bullet down to get the correct penetration while yielding enough energy transfer. Essentially, the best bet would be a bullet that just pops out of the back end of the intended target two make a wound channel that passes through both sides yet dumps all the force out into the target. A good permanent would cavity is also paramount.

Lastly, another method to increasing stopping power is multiple wound channels(reference the FBI's Handgun Wounding Factors and Effectiveness; MECHANICS OF PROJECTILE WOUNDING document). Hence why most are trained to conduct a 'controlled pair' on target. In order stop something, you want it's brain to run out of oxygen, which is carried by blood. By giving the blood a less restrictive way to go/losing blood pressure, the brain doesn't get any oxygen and then it's lights out.

Now, if you could get a pistol bullet that split on expansion after an inch or two of penetration and flew out of the business end of the firearm with some good speed, you'd be in the money(speed, energy transfer, and multiple wound channels).

http://www.firearmstactical.com/pdf/fbi-hwfe.pdf