Stopping power = Trauma
This is a discussion on Stopping power = Trauma within the Defensive Ammunition & Ballistics forums, part of the Defensive Carry Discussions category; I'm approaching the topic of stopping power from a more common sense standpoint. First off, any projectile out of a firearm will kill if it ...
March 28th, 2014 10:05 AM
Stopping power = Trauma
I'm approaching the topic of stopping power from a more common sense standpoint. First off, any projectile out of a firearm will kill if it hits something major like a COM organ (heart, lungs, liver etc), brain or central nervous system. The human body isn't exactly armor plated (we're wimpy compared to most animals of the same size) and any firearm can and have killed.
A standard FMJ projectile will act a lot like a BBQ skewer. It will drill a nice clean hole from entry to exit. FMJ 22LR, 9mm and most other rounds save .45 ACP (big and slow) will "skewer". And unless the skewering happens to be along the path of a vital organ or shatter an important bone (spine/hip), some people may not even notice they're shot. They may bleed out eventually but the wound would not be debilitating.
Now, take most of the major calibers designed to penetrate, expand and tumble within the body and the story changes. Those types of rounds cause trauma. Not so much like a BBQ skewer anymore but like a screwdriver driven into the body, and twisted and jerked around on the way in. I'll submit at this point that larger, faster moving and better designed (for expansion) rounds tend to achieve this effect better. Without naming calibers.
The trauma that a gaping, big and uneven wound causes would be what stops an assailant. Short of a hit to the vitals, there's no guarantee they'll stop, but trauma may cause the body to shut down or go into a state of shock whether or not a vital organ is hit. That would count as stopping power.
So a FMJ 10mm that "skewers" a nice clean hole thru an assailant will probably do close to nothing if it didn't hit a vital organ (at least nothing more than making a 10mm diameter hole). But a well designed high velocity expanding round of almost any defensive caliber (the slow but heavy .45 ACP being the only exception because it naturally pitches and yaws within human tissue) will cause trauma that will stop and incapacitate most human beings.
Feel free to discuss or add to this.
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March 28th, 2014 10:21 AM
I think sometimes we over think these things. People have been stopped for a long long time before we had all of these choices in ammo. I honestly find myself often over thinking it when I'm looking for ammo. Whats funny is I seem to over think it more when I'm looking for ammo for my wife.
March 28th, 2014 10:23 AM
The simple truth is that PAIN and FEAR are what stops most people. MOST stops with handguns are "psychological" as the victim was not rendered PHYSICALLY incapable of continuing what they were doing, they were , due to PAIN and FEAR rendered psychologically incapable of continuing and they choose to stop. Unfortunately some people are not afraid of anything and some due to psychosis, drugs , adrenalin, or alcohol feel no pain.
As to Trauma, bigger holes are better than smaller holes, and MORE holes is better than fewer holes. Given the choice I'd rather deliver more holes than fewer bigger holes (assuming we are discussing the difference in 9mm, 10mm and 11mm (9/40/and 45).
As to energy...handguns do not have enough energy to "knock people down". A .45 at the muzzle is 400 lbs of energy. A pro boxer hits with anywhere between 800 and 1200 lbs of energy.....so if they do not knock down their opponent with EVERY punch then how will a mere 400 lbs (1/2 to 1/3 the power of a good hook) knock anyone down? It doesn't. In fact a 1 lb weight falling 12 feet will deliver the same "knockdown power" that a .45 does at the muzzle....it is all scientifically measurable.
So what does this mean? Best results are going to be attained either using a rifle (which tend to deliver between 1500 and 3000 lbs or more of energy) or a shotgun (again 1500 lbs of energy AND multiple holes). If we are stuck with a pistol then best results are to punch multiple holes in important structures.
March 28th, 2014 10:28 AM
My first requirement in choosing ammo reguardless of caliber is does it feed well in my weapon. I normally will buy several boxes of different rounds that I have used in the past or a new one I want to try out. Than off to the range which ever feeds reliably I will be happy with. Than just practice till I am confidant I can draw hit com in under 2 sec than if happy with set up add to rotation. Thats about as technical as I get.
March 28th, 2014 11:40 AM
Penetrate and expand properly, and sufficiently.
Of suitable caliber/type to cause the most-effective incapacitating cavity, while remaining reliable.
Trauma being the indication of the latter aspect. The more damage to immediate surrounds, the better, from an incapacitation standpoint. In a deadly predator situation, the situation needs halting as quickly and effectively as possible. Such ammunition and placement are about the best options we have as defenders of innocent life.
Which brings us to theoretical and tested (lab) estimates of stopping power. Combined with relevant, credible "street" data, that's about as close as we're going to get to guessing how effective this or that cartridge/caliber is going to be.
About the most effective damage path I've seen from a 9mm cartridge in actual meat is: DoubleTap's 9mm JHP 124gr +P, through a side of beef. Makes a mess, big time, more reliably than several other "top" rounds I've fired through similar media. Anything similar should work just as well.
Your best weapon is your brain. Don't leave home without it.
self defense (A.O.J.).
How does disarming
the number of victims?
Reason over Force: Why the Gun is Civilization (Marko Kloos)
NRA, SAF, GOA, OFF, ACLDN.
March 28th, 2014 01:29 PM
Y'know, this is how every thread that devolves into a 'caliber-war' starts... "common sense".
Originally Posted by DetChris
March 28th, 2014 02:23 PM
DetChris, have you read Duncan MacPherson's "Bullet Penetration"? In it he attempts to examine the concept of what it would take to incapacitate a person WITHOUT a hit to a vital organ, and his premise sounds similar to what you're proposing - that overall shock and trauma to the body, even without direct damage to the CNS or major circulatory system, may possibly result in involuntary incapacitation of the person hit.
His premise is based on the old LaGarde steer tests, where steers were shot in (presumably) non-vital areas, and it was recorded as to how many shots it took before the steer dropped. The idea being that a steer wouldn't (or shouldn't) have the psychological triggers that humans have (being, we've seen so many movies where people fall down when they're shot, that we "know" that we're "supposed to" fall down when shot... a steer wouldn't "know" that).
MacPherson did extensive mathematical modeling to calculate exactly what happens when a bullet hits flesh, how it impacts and destroys flesh, how the flesh acts on the bullet to distort and deform it, and how the various bullet shapes contribute to how wounding occurs (i.e., a round ball is a much less effective wounder than a flat-faced cylinder like a true wadcutter). He then presents formulas for calculating how much tissue is destroyed by any given bullet, once you know how far the bullet penetrates and how large it expands to. He then "weights" that calculation against penetration factors, discarding damage that happens too shallow to be of any consequence, and discarding penetration that would be too deep and would likely represent overpenetration. And the grand result is what he calls the MacPherson Wound Trauma Indicator. It's a number that represents how much tissue was actually destroyed, where it counts, which would have an impact on disabling an attacker.
Based on relative weights of steer vs. humans, and how much tissue destruction it took to bring down a steer, he figured that it would take about 40 grams of tissue destruction to potentially cause an incapacitating hit on a human through shock and trauma. That's about equivalent to carving a hot dog out of a human body.
The nice thing about this idea is that it really doesn't care about caliber, nor contribute to caliber wars. It cares about the amount of tissue destroyed. Now, it's true that a 9mm FMJ is smaller than a .40 FMJ, which is smaller than a .45 FMJ, so caliber does play a very obvious role when discussing non-expanding bullets. But, if you had a case of a 9mm that expanded to .50", and a .45 that didn't expand and remained .45, and they both penetrated the maximum, then obviously the 9mm would create more tissue damage in that scenario. So it's not about "caliber", it's about amount of tissue damage.
Second, it doesn't all have to be done with one bullet. Damage is damage; if you have a bullet that does 25 grams of WTI, you could just shoot twice (and hit twice) to bring the level up to 50 grams of total trauma done. And, therefore, it includes inherently the more damaging aspect of a shotgun; 5 pellets of 000 buck would result in 80 grams of tissue destruction total, per pull of the trigger.
Now, this theory is disputed as well; since many 9mm hollowpoints are capable of delivering a WTI factor of 40 or more, and many .45 hollowpoints are capable of delivering a WTI of 60+, then by MacPherson's calculations, just about any hit with a 9mm or .40 or .45 hollowpoint should result in involuntary incapacitation -- and clearly they don't. So perhaps his calculation of the level of damage necessary was off? Or, perhaps the whole idea is wonky and there is no actual threshold of generalized, non-vital trauma that will result in immediate involuntary incapacitation? I don't know.
But I do know that it's a very useful and well thought out way for at least comparing the relative damage level of various projectiles. And I do firmly believe that the more damage done, the better. Obviously, the priority is to do damage to the vitals, and every shot should be attempted to hit the vitals as your first and sole priority. But not every shot will hit the vitals, and for those that do happen to still hit the body but miss the vitals, I'd rather that the non-vital shots were doing more overall destruction than less, and the WTI factor helps to figure out what the differences are in damaging capability between different rounds.
March 28th, 2014 02:33 PM
Originally Posted by Cruel Hand Luke
The mind is the limiting factor
Quick Kill Rifle and Pistol Instructor
March 28th, 2014 02:44 PM
Why do they call it common sense when it is rare and not common? I carry the largest and fastest caliber I can control well with factory JHP ammo that I trust.
I carry a gun, because a Cop is too heavy.
Second Amendment: The difference between politicians and rulers.
U.S. Army, Retired
NRA Benefactor Life Member
March 28th, 2014 03:23 PM
I guess I am stuck on the same old comment, placement and stop the threat.
March 28th, 2014 03:31 PM
Any caliber is capable of killing, but larger calibers are just a better choice in SD situations because they do more damage and end the threat quicker. A larger bullet will make a bigger hole.
March 28th, 2014 04:58 PM
I am sensing the same logic as... "All we need are some common-sense restrictions on gun availability..."
Originally Posted by 481
Not my circus, not my monkeys.
March 28th, 2014 05:28 PM
While that is true, psychological states are also one of the biggest reasons for FAILURE to stop. The way I see it, a psych stop is an unquantifiable factor, and therefore an unreliable one...so assume it won't work and be happy if it does.
Originally Posted by Cruel Hand Luke
I prefer fewer bigger holes. More shots fired = better chances of missing = better chance for a round going wild = more danger of a tragedy.
You pays your money and you makes your choices.
That being said--yes. More tissue damage means a better chance of them stopping whatever it was they were doing that made you decide it was necessary to shoot them.
There are no dangerous weapons; there are only dangerous men.--RAH
...man fights with his mind; the weapons are incidental.--Jeff Cooper
There is a reason they try and make small bullets act like big bullets--Glockmann10mm
March 28th, 2014 05:39 PM
I think someone got bored and decided to stir the pot.
March 28th, 2014 06:05 PM
I have a slightly different perspective. Coming from a scientifically trained background, I have looked at all the differing tests, and all the scientific testing of every parameter done by people with many points of view. I realized that well meaning people from different backgrounds, using well thought out testing processes, came to different conclusions. Often arguing over which type of bullet, caliber, and speed would give the quickest stop to a threat.
While scientific method is almost always the way to get the answer, there are times when it can
lead to more confusion.
So, I surmised the answer was best found in actual street gunfights by people who did this all the time and survived.
Among the gunfighters I examined, there were some more modern guys who spent years in law enforcement, and described what worked for them. Almost to a man, they seemed to favor speed and shot placement above all else.
But I went back a bit further to find someone who has been described as perhaps the deadliest gunfighter recorded.
John Wesley Harden could very well be considered my best source, as he faced gunfighters who were very often bent on killing him first.There is dispute as to how many kills he racked up, but historians agree he was one of the deadliest.
He attributed his success to constant practice to attain speed and accuracy. And he preferred head shots as the only guarantee of the first shot stop.
I have decided that, for me, that guiding philosophy works.
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