The 9mm vs 45 ACP Debate: A Visual Aid...

[pblanc]

But if, for the deaths, there is a significantly higher percentage of them in which a certain specific caliber was used, compared to the percentage of that caliber in the emergency room survivals, THEN that WOULD tell us something. Also, my comment was motivated by the fact that physicians working in the morgue can do a lot more exploring on their "patients" than physicians in the emergency room can do. That's also why I think some of the comments by handgun hunters on different observed wounds for different calibers can be useful.

You have a pretty good point. The authorities look down on surgeons who perform autopsies on living patients, regardless of how tempted we might sometimes be to do so. And people tend to get pissy when their surgeon makes an unnecessarily large and unnecessarily painful incision in their chest or abdomen so as to rule out a small possibility of a remote injury.

Pathologists do not operate under the same constraints and their subjects do not complain.

Of course, any study of gunshot wounds seen by emergency room physicians or surgeons is going to suffer from selection bias. The non-survivable wounds have already been selected out, with the exception of those DOA in the ER or trauma bay. Likewise, morgue data is going to suffer from selection bias.

When it comes to gunshot wounding mechanisms, I think all data needs to be considered.

For those who are interested, here is another citation to a journal from the UK that discusses treatment of high velocity military rifle wounds of the extremities. Again, a wound limited to an extremity is probably as close as one can get to ballistic gelatin. The article is long but here are a couple of extracts:

"Skin and muscle

These tissues are relatively elastic and therefore tolerate the temporary stretching effect of cavitation relatively well with limited tissue necrosis. Functionally, injuries to these tissues are also well tolerated."

"An injury with small entrance and exit wounds, no neurovascular compromise, and no evidence of fracture or bullet fragmentation on radiographs can be regarded as a simple through-and-through wound. It is likely in these injuries that there is a small amount of necrotic tissue in the permanent tract only and they can safely be managed minimally with irrigation, dressings, and prophylactic oral antibiotics. Consideration should be given to temporarily restricting use of the limb by plaster cast in order to protect the healing tissues."

The full article here:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4596205/

Once again, these are all high velocity rifle wounds being discussed. If the secondary cavity disruption that is routinely seen with ballistic gelatin with these cartridges often caused secondary muscle injury apart from the permanent tract, this type of management would not be possible.

 

[OldMarksman]

Medical examination data are probably really only relevant to this part of the discussion to the extent that they confirm the assertion, which may seem counterintuitive to some, that the differences in the width of permanent wound channels for different calibers are not very significant. We have heard that from pblanc.

Their usefulness in evaluating wounding effectiveness is limited. If we agree that wounding effectiveness is defined by the rapidity with which a bullet can seriously impair the ability of person to continue an attack, which involves the critical element of time, we cannot really learn much about wounding effectiveness just by looking after the fact at wounds made by individual bullets.

The limitations in the data reside in the following:

• there are far too many variables at hand in comparison with the number of persons shot; these include, but are not limited to, where each bullet entered and at what angle (theoretically that could be measured--there are just too many variations among the data), and the physical condition and psychological makeup of the attacker (which cannot be known);
• more importantly, and that's saying a lot, we would have great difficulty in determining which of the bullets hit in what order, and that would be critical;
• and still more importantly, after-the-fact examination cannot tell us the timing of the stop, or how far the attacker ran after each hit.

But suppose we could know all of that. Suppose that some magic information source had recorded all of that data, and that it could be retrieved and analyzed. What would we have? What would we do with it?

We would have a large number of multi-variate statistical distributions that would be nearly impossible to understand, and in my option, just about useless.

Here's why. If we were capable of analyzing it all, the data would tell us little more than what we already know. That is,

• if a citizen or police officer or FBI agent must use deadly force in what Rob Pincus calls a "dynamic critical incident", and he or she fires his firearm containing the latest and best 147 MM JHP ammunition, neither the number of rounds necessary to stop the assailant nor the distance the assailant will move can be reliably predicted in advance;
• if a number of similar incidents were to occur under very similar circumstances, the number of rounds fired and the distances would differ for each incident;
• and precisely the same things can be said about .40 and .45 ammunition.

We can really over think the subject of the relationship between wounding effectiveness and terminal ballistics. All we really need to know, in my opinion, is what kind of penetration and expansion performance in surrogate materials is likely to be necessary to effect the physiological damage that medical experts tell us is likely to be necessary to effect a stop. That does involve a lot of expert judgment.

Of course, it also involves a large number of variables. I would imagine that medical experts will make some simplifying assumptions to establish minimum boundaries. Assuming two layers of denim and assuming that a bullet will have to first penetrate an extended, clothed forearm are obvious examples.

Then we can factor in how many shots will generally have to be fired, and how quickly, to be likely to the damage parts of the body that medical experts tell us need to be damaged.

And then we can evaluate which gun and ammunition combinations best enable the defenders and agents and officers do all of that. That requires some range work. It also requires ammunition testing.

By the way, that's just about what was done in settling on the recommendation of the 9MM by the FBI.

 

[JohnKSa]

Yes a .452 projectile that expands to .8 will and create ... they would be able to tell the expanded .358 from a .452?

Assuming that the effects of temporary cavity are visible (and they may not be if the tissue is very elastic and/or there's not enough stretch to cause significant bruising), then an expanding handgun round wound will look quite different from a wound made by an FMJ handgun bullet.

FMJ rounds tend to create a temporary cavity that is pretty consistent in size and that decreases as penetration progresses. Expanding rounds tend to cause a significant temporary cavity during the initial phase of penetration that tapers down pretty rapidly.

This is because the rate of change of energy is very consistent, and not very significant with an FMJ/non-expanding round as it penetrates. That creates a fairly small and consistent temporary cavity that tapers down gradually. Expanding rounds have a much more abrupt rate of change of energy during the expansion phase and therefore they create a much larger temporary cavity during that portion of travel with a much more abrupt taper after the initial cavity.

You can easily find images online showing temporary cavities made by both expanding and FMJ handgun rounds and compare them.

Here are a couple.

FMJ round.

Expanding round.

 

[Radny97]

Thank you pblanc. Very helpful insight.

 

[Lohman446]

Ok now I'm confused when I am looking at those gel blocks with the fancy cavities and immense damage (like from the hollow points). At service handgun velocities does all of that count?

Also as has been noted most handgun encounters end because of psychological reasons and not physiological ones. We are discussing if its the medical doctors or morgue examiners we should be given the most credence to. I question if its either.

 

[OldMarksman]

Ok now I'm confused when I am looking at those gel blocks with the fancy cavities and immense damage (like from the hollow points). At service handgun velocities does all of that count?

Did not pblanc address that adequately?

Personally, I have never seen any evidence of significant wounding resulting from secondary cavities with handgun wounds of any caliber.

When I said "significant" wounds, I meant wounds that likely would have had an effect on immediate or early lethality or incapacitation.

It may be that handgun projectiles sometimes cause some tissue bleeding immediately adjacent to the bullet path but not anything that would be likely to result in increased lethality or quicker physiological incapacitation.

Human tissue does not behave like ballistic gelatin. Not only does it contain bone, it is not homogeneous. The closest thing to ballistic gelatin would be muscle tissue. But muscle and other human tissues contain elastin and collagen fibers that hold the structure together. Ballistic gelatin does not. Based on my experience, those sometimes impressive secondary wound cavities seen in ballistic gelatin do not have any counterpart in human tissues when it comes to handgun wounds.

Also as has been noted most handgun encounters end because of psychological reasons and not physiological ones.

How might that observation help us here? What prudent person would rely on "most?"

 

[Sharkbite]

We are discussing if its the medical doctors or morgue examiners we should be given the most credence to. I question if its either.

But there is absolutly NO WAY to quantify the factors that lead to a psychological stop.

Heck, we cant even agree on the physical ones

 

[Lohman446]

How might that observation help us here? What prudent person would rely on "most?"

Are you suggesting a handgun can stop ALL attacks? Because if not a good number of us are relying on most.

I just wanted to make sure we were going on the theory that all the fancy "damage" to the block was nothing more than visual noise and was meaningless. Tell me if you would about the great technology enhancements to bullet design that make modern bullets suddenly better if you would.

But there is absolutly NO WAY to quantify the factors that lead to a psychological stop.

Heck, we cant even agree on the physical ones

There is truth in at least the second half of this statement. We could discuss the first half though. Remember we are not discussing lethal hits with a handgun. Once we disregard psychological stops we are discussing hits that reduce the physiological ability to continue the fight quickly if not instantly. I think one of the strong arguments for 9MM is you are unlikely to get this out of any service handgun.

 

[Sharkbite]

There is truth in at least the second half of this statement. We could discuss the first half though.

Ok, lets discuss it. I always open to learning. How could we quantify how any given injury is "likely" to cause a person to "give up" the fight based not on injury/blood loss/trama to structures, but simply becsuse that shot overrode his WILLINGNESS to fight.

Second, how do we apply that to the human population at large? Different people have different abilities to cole with pain and different levels of motivation to continue the fight.

 

[Sharkbite]

Tell me if you would about the great technology enhancements to bullet design that make modern bullets suddenly better if you would

Read post #231. Others have corrected the time line of development, but the evolution is explained (to my limited knowledge)

 

[Lohman446]

Ok, lets discuss it. I always open to learning. How could we quantify how any given injury is "likely" to cause a person to "give up" the fight based not on injury/blood loss/trama to structures, but simply becsuse that shot overrode his WILLINGNESS to fight.

Any attack that stops prior to physical damage forcing the attacker to stop would qualify. How you would measure this experimentally might be an issue but we are basing a lot of assumptions based on a study of available data from the field and not from experimentally designed studies in this conversation anyways.

 

[OldMarksman]

Once we disregard psychological stops we are discussing hits that reduce the physiological ability to continue the fight quickly if not instantly.

Okay.

I think one of the strong arguments for 9MM is you are unlikely to get this out of any service handgun.

What???

 

[OldMarksman]

How you would measure this experimentally might be an issue but we are basing a lot of assumptions based on a study of available data from the field and not from experimentally designed studies in this conversation anyways.

What study, from what available data from the field?

Read Post #262.

 

[noonesshowmonkey]

These debates are hilarious.

The medical links provided thus far are perhaps the best (and only) evidence provided thus far.

If we are talking about wound tracks and calibers and terminal ballistics (oh my!), we're talking about killing. Thus far, I am not sure if there has been any serious discussion about killers and their selections, much less the reasons for such selections.

An acquaintance who is in the mexican federal police, and has more than a few notches on his belt, got all of his kills using FMJ 9x19mm. He just dumped (LOTS of) rounds into their chest/face.

The SOF buddies that I have carry 9mm Glock 19s. My agency issues .40.

The short answer is that people that hunt other people give hardly a single drizzling crap about what has been wrapping people around the axle for the past however many pages.

If you are an armed professional, your agency/unit determines what you carry. If you are a private citizen, carry what ever makes your Johnson feel stronger / longer / more powerful.

Medically, the laws of physics look down on handgun rounds, regardless of their caliber. Even at maximum expansion, the wound track has to hit something vital, which is better controlled by placement than anything else. Even before that, you need to be able to achieve hits under stress, and probably while moving. If I could only get one hit, once, ever, on a target, sure, I'd get the biggest one I could. Make it a cannonball.

But, that isn't the real world.

The answer has been for a while now capacity to achieve hits, the placement of those hits, and the volume of hits delivered into vital locations.

If you want a round that has better wounding characteristics, pick up a rifle. 77gr OTM Mk262 has been killing people for a while now, and doing it really very well.

 

[OldMarksman]

If we are talking about wound tracks and calibers and terminal ballistics (oh my!), we're talking about killing.

Not at all. We are concerned effectively stopping a violent criminal actor. He may die--or not; likely not. Lethality is not the objective.

If you are an armed professional, your agency/unit determines what you carry.

Yep.

If you are a private citizen, carry what ever makes your Johnson feel stronger / longer / more powerful.

For many, that's unfortunately true. I prefer an informed decision.

Medically, the laws of physics look down on handgun rounds, regardless of their caliber. Even at maximum expansion, the wound track has to hit something vital, which is better controlled by placement than anything else. Even before that, you need to be able to achieve hits under stress, and probably while moving.

Yup.

If I could only get one hit, once, ever, on a target, sure, I'd get the biggest one I could. Make it a cannonball.

Can't argue with that.

The answer has been for a while now capacity to achieve hits, the placement of those hits, and the volume of hits delivered into vital locations.

Almost. Don't forget penetration.

 

[noonesshowmonkey]

Here is a dirty, dark secret of 'stopping the threat': that means killing someone. If they stop before you kill them, huzzah. But, law enforcement doesn't shoot at someone (ie use LETHAL force) unless they are in a lethal, as in deadly, engagement. Should the situation resolve before the other party is killed, gravy.

The military has no such qualms, and just kills people.

The private citizen is not bound by the same policies and public scrutiny that LE is, but also does not operate outside of the CONUS, in a time of war as does the military.

Either case, I can't tell you what makes a man quit. I can, however, say that if you pass a high velocity projectile through his media stinum or mid/lower brain, he typically quits in a real hurry.

And yes, penetration was taken for granted in my listing of characteristics. The round must be able to penetrate far enough into its target to actually strike something vital. Luckily, modern bonded JHP rounds can be had that go plenty deep and also expand such as to make penetration less of an issue.

 

[OldMarksman]

Here is a dirty, dark secret of 'stopping the threat': that means killing someone.

That means employing deadly force-- which entails a significant risk of killing.

The majority of persons shot with handguns these days survive.

 

[Lohman446]

Here is a dirty, dark secret of 'stopping the threat': that means killing someone

Not really. When I say I intend to fire until the threat stops I intend to fire until the threat stops or the situation changes enough to allow me to retreat.

While I acknowledge that the force I would use is lethal and may result in death it was not my intention and I would only use that level of force if given no other option. I greatly prefer that the attacker live.

 

[Mike_Fontenot]

Any experience with actual wounds from the new (very expensive) solid copper bullets with the odd shapes scouped out of the front? For a while, I thought they were probably nothing but hype, but several independent testers I've seen seem to be duly impressed. Underwood sells some that he says have about twice the "permanent wound cavity" that conventional lead-core JHP's, with the same energy, have. I assume that means a permanent cavity that remains in ballistic gelatin. And from some of the posts on this thread, it sounds like those cavities that remain in gelatin don't (usually) show up in real tissue wounds. I'm guessing that those copper bullets are so new that there isn't any actual wound experience with them.

 

[CDW4ME]

Barnes / Corbon DPX copper bullet 160 gr. 45:
https://www.youtube.com/watch?v=dyAh-sIHhW0