Interesting Stopping Power article/study

[THplanes]

This is a pretty good place to start with comparing calibers, and how they might effect a target.

http://brassfetcher.com/index_files/Page1950.htm

Something that isn't brought up much is the ability of heavy bullets to maintain their speed through a target, creating secondary projectiles out of bone increasing the wounding effect.

Someone mentioned that non-expanding bullets aren't very effective as stoppers. I beg to differ. Depending on bullet shape, weight, and velocity you can
create a very large, and effective hole.

This is an exit wound created by a 440 grain, .500 caliber LFN, at 950fps(.500JRH). The effect on the animal was compared to a .375 H&H rifle.

Here is a .452" LFN hole that proved fatal:


.45 Colt, LFN, 1150 fps.
Wound channel is a function of bullet design, VELOCITY, and bullet weight.

While you can't come up with a magic bullet, you can now come up with calibers, bullets, and velocity in pistols that hit like rifles.

Perhaps instead of ending with .45 caliber, we should use that as a starting point and go up.

This one says it all:

http://www.youtube.com/watch?v=xYSGuiko6Gg&feature=related

Sorry, that can't happen at those velocities.

Fackler said it
I believe it
and that's that

 

[481]

I would suggest that the surface area of the permanent crush cavity is a better measure of wounding than the crush cavity. Pulped tissue doesn't bleed, other than the blood actually in the destroyed tissue. The surface of the wound is what bleeds.

MacPhersons book is from 1994. There was a second printing in 2005. I've just started reading it so I can't comment on it yet.

Since the surface area of the permanent wound cavity is a function of the permanent wound cavity's length and circumference, it is directly proportional to the volume of the permanent wound cavity (and its volumetric mass) and as such, is already accounted for in MacPherson's model.

 

[Prosser]

Fackler said it
I believe it
and that's that

It's horrible when real observations get in the way of theory.

If you start looking at Beartooth's wound channel calculator, it starts making sense. You get a real good jump in wound channel when you move into the 1100-1350 fps range, and, another boost since at the higher velocity, the big cast bullets start to mushroom:

Third from the left is a 500JRH load that hit a buffalo at 1350 fps, 430 grain bullet, and penetrated 6 feet.
So, you get an increased wound channel from velocity, bullet design, mushrooming of an LFN that's already huge to begin with, not to mention that the cavity is created by the bullet blowing a huge hole, at near constant velocity through the target, vs. service calibers that loose all their energy in the first 8" of penetration,and what everyone has observed for 100 years, that there is a HUGE difference in effect between .45 caliber, and the .475's, .500's, and .510's.

We now have handguns that are so far outside the service caliber box that one has to remember they are there. Also, no one has really explained why
big, well, huge, .475 and .510 caliber bullets are so much more effective
then .45's, at slow-medium velocities, read 950-1500 fps.

They guys that hunt with this stuff have observations on large animals that don't make much sense. Why would a 525 grain, .510 caliber LFN, at 1100 fps, kill better then heavy rifles?

 

[gvf]

So can you point me to the psychological studies that support these claims. As a secondary question, even if all rapid incapacitation that doesn't come from a CNS hit is psychological in nature, where are the psychological studies that demonstrate caliber and load make no difference.

Do we attribute a deer shot with a service caliber handgun, non CNS wound, falling in a few seconds to deer TV.

You'd have to ask the FBI. It's their document. I quoted it because I believe they are reliable.

It wouldn't surprise me if their observation was based on.... professional observation, rather than a Psychological study. They certainly have done a lot of thorough assessments of actual shootings if you read the entire document. Nor is it difficult to reach such a conclusion from post-shooting analysis of the wound as well as the behavior of the wounded. They apparently often do not correspond. And interviews after would give valuable info on the subjective awareness of the wounded participant.

It's also fairly common for non-experts, the public including interested shooters like us, to hear of the same phenomena, in news stories, or on internet forums dealing with the subject of SD shootings, or from other places.

One point: the conclusion about "propensity of many to fall-down when shot" - irrespective of the wound - the FBI states is "many", not "all".

What I find suspicious in is not so much the FBI's conclusions as your reaction to them. It appears these make you angry and demanding. You must have a need to believe you can determine, through caliber or other choice, the outcome of an extremely complicated event that does not exist at the present time and likely never will . Otherwise, the usual reaction - relief that a would-be killer may well succumb to any shot - would be there.
***
-As to your comparison to deer, though offered mockingly, it actually supports the conclusion in the report. An animal will either fall or not fall purely based on the wound. So the behavior and the wound would correspond - and you'd almost surely find that in shootings of animals would you engage in a study of them when shot. If the wound was minor or in a place that did not physically cause the animal to fall: it wouldn't.

But in fact humans do do that: fall for no physical reason. And humans also have much more sophisticated psychological mechanisms than deer, capable of reacting to memory rather than the moment, or to memories of images from TV and film of a shooting victim falling, or to creating instant connections between sensation and imagined results. Deer can't do any of that. And that's why humans falling down with no observable physical basis for doing so, must, in fact, fall down on the basis of psychological perception.

Without knowing you were doing so: your deer analogy supported the conclusion you wanted to dismiss.

 

[Tape]

HERES The original website that wrote the artical, Buckeye Firearms Association it has pictures and graphs if anyone is interested.

 

[Tape]

Fall down?

Stopping power?

In Honolulu a troop got out of a UH-1 helicopter which had landed on the side of a hill. The troop ran "up hill" and the rotor blade took his head off a cleanly as any guillotine. The body continued to run another 4 steps before falling.

was the head itself decapitated or was it from the neck up?

 

[Prosser]

Weird stuff, deer. How about a .475 LFN, at 1350 fps, 420 grains, that hits the ham, goes length wise, misses all vitals, yet the deer falls over, dead

Similar deer, has heart blown out with a .300 Magnum, yet goes 100 yards before falling over, dead.

It MUST be the TV...

Keep in mind that the FBI's box is restricted to service caliber weapons, and, they face some REALLY bad guys, and girls.

Also, I can't help but think that LEO had the perfect firearm, the .41 Magnum but it was removed from service for a number of reasons.

If you read inbetween the lines, you can see the FBI guys focused on one problem: In service calibers, with hollow point bullets, it's very difficult to come up with a combination that penetrates far enough for them, that ideal 18" of gello. It's pretty amazing how velocity combined with light hollow points limits penetration.

 

[Loyalist Dave]

No matter what gun you are shooting, you can only expect a little more than half of the people you shoot to be immediately incapacitated by your first hit.

Actually this is an erroneous conclusion, based on spurious information. First it is admitted that the projectile type was unknown. Other factors to consider:

Barrel length, some handgun bullet designs perform better at higher impact velocities, and longer barrels in some handguns increase MV and thus increase impact velocity.

Was the sample all from "gunfights" or did he include homicides?

Finally, what was the training level of the shooters? I have seen VAST differences between differing agencies of Law Enforcement, Law Abiding Citizens, Thugs, Peacetime Military, and Combat Vets when it comes to accuracy with a handgun under fire.

The study shows little about the type of handgun caliber, and more about the persons shooting (imho). It demonstrates that on average when people in the geographic area where the sample was taken shoot at a person, they have a 50% chance of "immediately incapacitating" the target. The problem with the data is that it includes people with little training and possibly those with a high level of training. (I know it includes people with little training, for the vast majority of gun owners would fall into what I would consider "little training" - my opinion)


Examine reports of 100 civilians who compete on a regular basis in IDPA, or TSA that have been involved in a fatal shooting, reports of 100 law enforcement officer fatal shootings, and reports of 100 folks involved in fatal shootings with only the basic knowledge of how to load and fire..., the data will skew toward the civilian competition shooters (again imho).

In short, it's not simply the cartridge that one uses for SD, but whether the person can hit what they shoot at. IF you want to be successful in an SD situation, you need a good, accurate cartridge/handgun..., and you need to train on a regular basis.

Which has been known for many decades.

LD

 

[fastbolt]

I remember when I was issued a copy of SA Patrick's Handgun Wounding Factors and Effectiveness when it was still pretty new (back in '90). I had a bit less than a decade of LE experience at the time and was a brand new firearms instructor.

More than 20 years later I still consider it to be an excellent read (as a primer) and to have withstood the test of time.

 

[THplanes]

Since the surface area of the permanent wound cavity is a function of the permanent wound cavity's length and circumference, it is directly proportional to the volume of the permanent wound cavity (and its volumetric mass) and as such, is already accounted for in MacPherson's model.

No it's not, you are once again wrong. For the other instances we would have to go to another forum. Take a wound with a radius of r and a length of L.

The surface area and volume are

Sa = (pie)2rL
v = (pie)(r^2)L

If we double length we use 2L for the new length, the surface area and volume are

Sa = (pie)2r2L so the surface area has doubled
v = (pie)(r^2)2L so the volume has doubled


If we double the radius we use 2r for the new radius, the surface area and volume are

Sa = (pie)(2(2r))L so the surface area has doubled.
v= (pie)((2r)^2)L so the volume is increased by a factor of 4

This neglects the surface area for the ends of the cylinders. I believe that's reasonable because the entrance is a hole and holes don't bleed. If the bullet exits the same is true. For a bullet that does not exit you add (pie)r^2 to the surface area. For cases where L is large in comparison to r we can neglect this small area. This is usually the case for service caliber handgun rounds.

So if you double length of the wound track you get twice the surface area and twice the volume. If you double the radius of the wound you get double the surface area and four times the volume. Clearly there is not a direct relationship between volume and surface area. In the case where you double surface area by doubling the length of the wound you also get a doubling of the volume. In the case where you double the surface area by doubling the radius, you get four times the volume.

I don't really like this because I like the bigger bullets make bigger holes concept. This shows the increase in volume that comes from and increase in the radius of the wound overstates the relative increase in bleeding surface area.

I've just started reading MacPherson's book so i don't know how he covers this. But another problem is the new stelate shaped bullets. IMHO, the manufacturers seem to want us to infer the sharp tips will leave a larger wound. Do these bullets actually leave a stelate shaped wound which would also increase wound surface area.

 

[481]

No it's not, you are once again wrong. For the other instances we would have to go to another forum. Take a wound with a radius of r and a length of L.

The surface area and volume are

Sa = (pie)2rL
v = (pie)(r^2)L

If we double length we use 2L for the new length, the surface area and volume are

Sa = (pie)2r2L so the surface area has doubled
v = (pie)(r^2)2L so the volume has doubled


If we double the radius we use 2r for the new radius, the surface area and volume are

Sa = (pie)(2(2r))L so the surface area has doubled.
v= (pie)((2r)^2)L so the volume is increased by a factor of 4

This neglects the surface area for the ends of the cylinders. I believe that's reasonable because the entrance is a hole and holes don't bleed. If the bullet exits the same is true. For a bullet that does not exit you add (pie)r^2 to the surface area. For cases where L is large in comparison to r we can neglect this small area. This is usually the case for service caliber handgun rounds.

So if you double length of the wound track you get twice the surface area and twice the volume. If you double the radius of the wound you get double the surface area and four times the volume. Clearly there is not a direct relationship between volume and surface area. In the case where you double surface area by doubling the length of the wound you also get a doubling of the volume. In the case where you double the surface area by doubling the radius, you get four times the volume.

I don't really like this because I like the bigger bullets make bigger holes concept. This shows the increase in volume that comes from and increase in the radius of the wound overstates the relative increase in bleeding surface area.

I've just started reading MacPherson's book so i don't know how he covers this. But another problem is the new stelate shaped bullets. IMHO, the manufacturers seem to want us to infer the sharp tips will leave a larger wound. Do these bullets actually leave a stelate shaped wound which would also increase wound surface area.

Lighten up.

You are gonna pop a major blood vessel (or worse) with all that

The proportionality that I described in one sentence (post #27) required several paragraphs and repetitive equations for you to duplicate it in your post (post #35).

So if you double length of the wound track you get twice the surface area and twice the volume. If you double the radius of the wound you get double the surface area and four times the volume. Clearly there is not a direct relationship between volume and surface area. In the case where you double surface area by doubling the length of the wound you also get a doubling of the volume. In the case where you double the surface area by doubling the radius, you get four times the volume.

You have contradicted yourself.

You say (highlighted red) there is no direct relationship between volume and surface area, yet you go on to describe (highlighted blue) four such direct relationships between volume and surface area. Which is it?

 

[bassdogs]

I recall a comment made by the instructor at my CC class a few years ago. He was the police chief of a small town nearby and noted that the shoot and the BG drops is pure Hollywood. When ask why he shot a bad guy 6 times during a gunfight, his response was "I ran out of bullets".

Think the real issue here is that when confronted with a threat to your life or well being, you should use what ever force you have at hand. Taking 1 or 2 shots and stopping to see if the BG is down might well get you killed. Arguing about 1 shot stopping power is really a fools folly. You're not going to walk around with a .50BMG so carry just about any service caliber and practice to be confident with it.

 

[Prosser]

There are options now which are packable, and pretty much WAY outside the service caliber
box.

Every guy that ever jumped me, and were not many, were huge, 240-300 pounds. Use something for that size animal, and, you are golden.

 

[Loosedhorse]

Sa = (pie)(2(2r))L

Mmmmmmm. Pie. [Drool.]

The reason that mathematicians stay thin is they like pi, not pie.

In any case, I am glad you cleared that up. I am sure if we explain that to anyone wounded with the right round, they will quickly realize they should be incapacitated, and will decide their only logical choice is to fall down.

 

[THplanes]

You have contradicted yourself.

You say (highlighted red) there is no direct relationship between volume and surface area, yet you go on to describe (highlighted blue) four such direct relationships between volume and surface area. Which is it?

Come on 481 don't play word games with me. There is a direct relationship between between change in surface area and change in volume only when the change is caused by increasing the length of the wound. When you change volume by increasing the radius of the wound the relationship of surface area to wound volume is exponential.

 

[Prosser]

Thanks for the link to the original. After reading that, I'm out. Rarely have I had a chance to read such garbage, at least since the S&M "Statistics".

You don't have the time to figure out which load? Give me a break. The entire story is about bullet weight, velocity, and bullet design, and, pretty much least, bullet caliber, unless you are comparing LFN's or cast bullets, and, we aren't smart enough to be doing that in that article.

All I have to say is that the old swiss rifle round, 300 grain soft lead, at 1300-1400 fps, in .41 caliber, was one of the most lethal rounds ever in combat.

Use that as a model, and, you might have something...

 

[2ndAmFan]

My opinion, based on no science whatsoever is that a 124 grain 9mm Luger +p hp, traveling at an approximate velocity of 1200-1400 fps, placed properly should do the job. So would a lot of other rounds. Shot placement counts above all.

 

[Mike1234567]

In all my reasearch what I've learned is the most important thing is shot placement followed by penetration followed by would channel destruction. IMHO, .380 is a marginal round while a good 124gr 9mm HP is nearly as effective as a good 230gr .45 ACP HP. IMHO, since most folks won't be accurate enough in a SD situation to guarantee effective shot placement, then more destruction per shot is helpful. So... I keep a .410ga shotgun and .45 ACP handy at home but I carry a 9mm (only on my property and in my car until I attain my CHL).

 

[TenMillimaster]

http://www.rathcoombe.net/sci-tech/ballistics/wounding.html

I've posted that link before but plenty of good info there.
As far as incapacitation or stopping power, knockdown power go... I don't buy it, not one bit.
Energy is another acceptable way to look at wounding effectiveness IMO as long as you consider that there's plenty of other work a travelling projectile can do that isn't wounding.

As far as the site the OP posted, I don't consider any of that statistically reliable, as it's still a collection of anecdotes. No control over conditions and unreliable data. Aren't there some studies that have used live pigs? I'd trust information gleaned from them much more.

 

[2zulu1]

No it's not, you are once again wrong. For the other instances we would have to go to another forum. Take a wound with a radius of r and a length of L.

The surface area and volume are

Sa = (pie)2rL
v = (pie)(r^2)L

If we double length we use 2L for the new length, the surface area and volume are

Sa = (pie)2r2L so the surface area has doubled
v = (pie)(r^2)2L so the volume has doubled


If we double the radius we use 2r for the new radius, the surface area and volume are

Sa = (pie)(2(2r))L so the surface area has doubled.
v= (pie)((2r)^2)L so the volume is increased by a factor of 4

This neglects the surface area for the ends of the cylinders. I believe that's reasonable because the entrance is a hole and holes don't bleed. If the bullet exits the same is true. For a bullet that does not exit you add (pie)r^2 to the surface area. For cases where L is large in comparison to r we can neglect this small area. This is usually the case for service caliber handgun rounds.

So if you double length of the wound track you get twice the surface area and twice the volume. If you double the radius of the wound you get double the surface area and four times the volume. Clearly there is not a direct relationship between volume and surface area. In the case where you double surface area by doubling the length of the wound you also get a doubling of the volume. In the case where you double the surface area by doubling the radius, you get four times the volume.

I don't really like this because I like the bigger bullets make bigger holes concept. This shows the increase in volume that comes from and increase in the radius of the wound overstates the relative increase in bleeding surface area.

I've just started reading MacPherson's book so i don't know how he covers this. But another problem is the new stelate shaped bullets. IMHO, the manufacturers seem to want us to infer the sharp tips will leave a larger wound. Do these bullets actually leave a stelate shaped wound which would also increase wound surface area.

Would you agree with this assessment?

While sectional density is part of the overall terminal performance picture, that parameter is "redefined" at/during expansion. Penetration depth is inversely proportional to the expanded cross-sectional area of the recovered bullet and directly proportional to the velocity of the bullet at the instant of impact. The dimension of the frontal area of the expanded bullet induces drag (effectively behaving as a "brake" as it traverses the media) and when this dimension increases (final expansion diameter) drag increases by the square of the difference in the expanded radius which is effectively ΔA = πΔr2


Therefore, while the effect of the difference between the 10mm's and the .45's final expanded diameter might seem insignificant, it isn't.

The sectional density for each respective round decreases significantly and the one that expands proportionately less than the other gains an advantage in its 'new' and somewhat greater sectional density.

Numerically speaking, the 10mm's sectional density decreases from 0.16071 to 0.05278 (33% of its prior sectional density) and the sectional density of the .45 decreases from 0.16118 to 0.07105 (44% of its prior SD) allowing the .45 load to destroy 6.25% more soft tissue and penetrate 1.33 inches farther/deeper than the 10mm despite the 10mm load's greater KE (+214 fpe/ +53% more than the .45).

This phenomena clearly demonstrates why a "momentum" model is a better means of quantifying hard terminal ballistic performance than an "energy" model.

10mm 180 gr. Remington Golden Sabre JHP
Impact velocity: 1243 fps/618fpe
Average recovered diameter: 0.698"

Vcav = 389.302 fps
Mw = 58.906 grams (2.078 ounces)
Xcm = 33.361 cm (13.134 inches)

.45ACP Winchester Bonded PDX1 230 gr. JHPImpact velocity: 889 fps (404fpe)
Average recovered diameter: 0.680"

Vcav = 392.366 fps
Mw = 62.603 grams (2.208 ounces)
Xcm = 36.748 cm (14.468 inches)

Bob

 

[I'm3rd]

I suspect that there are many more factors involved in the way a bullet wound stops an attacker or fails to stop him than the diameter, weight, velocity, metal type, and design of the bullet itself. I think that in many cases the shooting victim's mental, physical, and/or emotional state at the time he is shot probably has as much, or maybe more positive or negative affect on his ability to continue fighting as the actual physical damage to his body does. When non-ballistic factors such as drugs, alcohol, fear, rage, pain tolerance, overall health, personality, etc are stirred into the equation the wounding effect of the bullet itself may not be the primary factor that determines it's good, so-so, or poor stopping power.

Now after having said all that, I will admit that if I knew, or even strongly suspected that I would be involved in a shooting incident tonight I would be carrying my 1911 .45 instead of my Keltec .380 when I leave home.

 

[Cosmoline]

According to those data, I should carry a shotgun everywhere. So....

Or a rifle, absolutely. But you probably can't, which is the only reason for a handgun.

Within the range of typical CCW pieces--from .45 ACP to .32 ACP, it probably doesn't make that much difference which you use.

 

[481]

Come on 481 don't play word games with me.

Given the events of the past twenty-four hours (let's leave it at that for the sake of discretion), I have engaged in no "word games" with you simply because there is no point in provoking you.

I quoted your post (presently post #35) in its entirety and then highlighted (in "red" and "blue") the relevant portion of the post to which I was referring to specifically for the sake of clarity. It is all there (albeit in "red" and "blue") just as you typed it.

If you wish to retreat from any part (or all) of the self-contradictory statements made in your post, you certainly don't need my permission.

 

[Strykervet]

I read an article written by an ex-cop murder detective turned pathologist. He carried a 9mm the whole time he was a cop. When he started working in the morgue and seeing all the gunshot victims in Atlanta, he switched to the .45ACP. He said most of the time, 9mm victims had multiple gunshot wounds, whereas the .45ACP victims tended to have just one or two wounds. Not to mention the difference in damage caused by the round.

I like the 10mm myself. 9mm is fun for the range and useful for reduced recoil and/or high capacity. But I think once you hit .40S&W and .357mag, you are in the realm of true defensive rounds where provided you hit your target and use a suitable loading it will do the job almost as good as the next. Some are better for certain shots, ie, high velocity and energy work better on nerves whereas fat heavy and slow bullets work better at breaking bones and punching holes.

And that is why I like the 10mm. As fast as a .357mag but makes bigger holes with heavier bullets, greater sectional density and better ballistic coefficient than .45ACP. Greater kinetic energy than both, and more capacity than both.

Could it be the perfect round, dare I say?

 

[Prosser]

NO. Doesn't do heavy bullets well enough. .451 Detonics, or .45 Colt/.454 low end rounds, yes.