Why The Obsession With "One Shot Stop" Statistics?

[skb12172]

If I ever have to shoot someone in defense of myself or others, I'm sure as heck not gonna just shoot once. Two, or more likely, three will be the order of the day. Repeat as necessary, depending on the bad guy stopping pronto.

So, since Kim as well as many others have acknowledged that anything in the .38/9MM range or higher will probably suffice, why do we still hear so much about one shot stopping capability? Especially given that even a single .45 round has been shown to be insufficient, given the right circumstances.

Fire Away!

[Frankingun]

I think it's just a tacticool trend.

[Rod]

It's just something that sounds as good as one stop shopping.

[randy]

From a former air/to surface weapons geek perspective, theoretically, the percentage of one stop shots for a given round would be useful for comparison with other rounds in making a decision of which ammo to choose (I might note 1 factor, not the only one) within a caliber, and in choosing a caliber in the first place.

A 90% rating would be preferable to a 50% for instance. The higher the one stop percentage the higher the percentage of stops from multiple rounds (and no, 2 90% rounds do not equal 180%, I'm too lazy to look up the formula right now).

In the real world, the problem is quantifying that data. It's hard to come by, almost never in a scientifically measurable situation, and there are so many variables (adrenaline, drugs, clothing, training, etc) it's almost impossible to account for them all. The few studies/projects that have tried are controversial and limited in scope. And many question the whole premise, preferring to use laboratory friendly standards such as penetration of ballistic gelatin (Morgue Monsters vs Jello Junkies).

In the Air to Surface world, we developed effectiveness percentages of each component (warhead, guidance, fusing, etc) based on actual results since WWII, laboratory and field tests, and SWAG (because the Murphy Factor is always 100%). The current data is the result of millions of man hours, probably billions of dollars and countless lives (operationally and on the ranges) lost. I don't see anyone putting that kind of resources into this type of study for handgun ammo. From the .gov bean counter perspective, small arms ammo and shooters are too cheap to replace to put that kind of effort into.

So, I find the concept valuable, but on a practical level not likely to be really useful based on the current state of the art.

[MarkD]

It's basically just a way of comparing two cartridges, of determining which cartridge is more "effective" by basically defining effectiveness in a very limited way. I can think of worse methods of comparison than "stopped the target with a single round to the torso x% of the time". You can gather statistical data on that. The problem is sample size, can you state with any certainty that a cartridge that stopped with one-shot three times out of four cases is better than one that did so two time out of four? Is it equal to a cartridge that did so 750 times out of 1,000?

[Combat Controller]

Because if you only manage to hit once you want it to really count?

[Rusty Ray]

OK one would guess that it is important if you consider that say 3 shots from the average wonder nine leaves you (mostly) with still over ten rounds left. But three shots from .45 single stack leaves you getting low, and it is even worse for a revolver.


Rusty

[mekender]

the importance comes into play when you realize that the person you shoot is also likely to be attacking you... the goal of shooting them is to make them cease their attack as quickly as possible so they can do no further damage to you...

everything ive ever read on the subject of lethality says that .22's are fine man killers, thousands or even millions of corpses throughout history can attest to that... but those men typically die hours later on an OR table... if your attacker takes 3 hours to die, that means that he can spend that time attacking and even killing you...

now, i have seen video of police shootout suspects that were hit upwards of 15 times with handgun rounds in center mass and they continued to shoot back... one even survived and was on the news with at least 8 holes in his torso, smiling as he was led off in handcuffs... ive posted those links here in the past...

also, smaller, lighter bullets tend to be easier to deflect off of bone... this means a greater chance of the round glancing off and out of the body before it can do vital damage... heavier, slower rounds carry more energy and tend to smash through bone without a lot of deflection...

expansion is also a factor... the more expansion there is, the more likely the round is to remain in the target, the more energy the round dumps into its target... there is a lot of research still being done on how the hydrostatic shock can cause wounds far from the actual wound tract, so its rather unclear as to all of the effects...

the bottom line, almost any major brand JHP round will do just fine for defense...

[Aglifter]

500 S&W light mag... Only way to be sure... (And even that might fail... maybe...)

[mekender]

500 S&W light mag... Only way to be sure... (And even that might fail... maybe...)

well as ive said before... if i only get one shot, i would want a phased plasma rifle in the 40w range... but since i will probably get more than one, a 9mm with a good JHP will be fine...