Basic Wound Ballistic Terminal Performance Facts

I almost dont believe this article since theres no mention of 9mm vs .45

(From the article)

Dr. Gary K. Roberts


"The last 30 years of modern wound ballistic research has demonstrated yet again what historical reports have always indicated–that there are only two valid methods of incapacitation: one based on psychological factors and the other physiological damage. People are often rapidly psychologically incapacitated by minor wounds that are not immediately physiologically incapacitating. Psychological factors are also the reason people can receive severe, even non-survivable wounds and continue functioning for short periods of time. Up to fifty percent of those individuals rapidly incapacitated by bullet wounds are probably incapacitated for psychological rather than physiological reasons. Psychological incapacitation is an extremely erratic, highly variable, and completely unpredictable human response, independent of any inherent characteristics of a particular projectile.

The degree and rapidity of any physiological incapacitation is determined by the anatomic structures the projectile disrupts and the severity of the tissue damage caused by the bullet. Physiologically, immediate incapacitation or death can only occur when the brain or upper spinal cord is damaged or destroyed. The tactical reality is that in combat, opportunities for military personnel to take precisely aimed shots at the CNS of enemy combatants is rare due to high stress unexpected contact marked by rapid fleeting movements, along with frequent poor visibility on the battlefield including use of cover and concealment. Thus the reduced likelihood of frequent planned CNS targeting in combat conditions. Absent CNS damage, circulatory system collapse from severe disruption of the vital organs and blood vessels in the torso is the only other reliable method of physiological incapacitation from small arms. If the CNS is uninjured, physiological incapacitation is delayed until blood loss is sufficient to deprive the brain of oxygen. Multiple hits may be needed before an individual is physiologically incapacitated. An individual wounded in any area of the body other than the CNS may physiologically be able to continue their actions for a short period of time, even with non-survivable injuries. In a 1992 IWBA Journal paper, Dr. Ken Newgard wrote the following about how blood loss effects incapacitation:

A 70 kg male has a cardiac output of around 5.5 liters per minute. His blood volume is about 4200 cc. Assuming that his cardiac output can double under stress, his aortic blood flow can reach 11 Liters per minute. If this male had his thoracic aorta totally severed, it would take him 4.6 seconds to lose 20% of his total blood volume. This is the minimum amount of time in which a person could lose 20% of his blood volume from one point of injury. A marginally trained person can fire at a rate of two shots per second. In 4.6 seconds there could easily be 9 shots of return fire before the assailant’s activity is neutralized. Note this analysis does not account for oxygen contained in the blood already perusing the brain that will keep the brain functioning for an even longer period of time

(Click link to view full article)


BUT! BUT! BUT! THE MORO REBELLION! THEY DUSTED OFF OLD .45’s AND ENDED THE FIGHTING!!! Everyone told me .45ACP is a ‘man stopper’ and only requires one hit anywhere on the body :roll_eyes:

In all seriousness, search YouTube for Paul Gomez(Gomez8136). He posted quite a few videos that broke down much of the research from Doc.G.K.R. prior to his passing.


Oh shit…you went there :popcorn:

We had one of these discussions last week.

Honestly, I like .45 cap and view the debate like this:

.45 ACP fmj > 9mm fmj

Quality 9mm > .45 ACP fmj

Quality .45 ACP = Quality 9mm, the .45 has better performance shot for shot but the 9mm has better capacity. Neither is really better than the other as long as you can shoot both accurately , imo.

But…just to keep up with my reputation

9mm > .45 acp, but 10mm is king.


I almost dont believe this article since theres no mention of 9mm vs .45

Dangerously close to a false dilemma. The article is about how stupid it is to think there is only 5.56 and full size 30.06, or 7.62 NATO. Intermediate rifle rounds are quite effective on the 2 way range and in ballistic testing.


I was making a joke, not being literal. You are correct though.

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Sarcasm doesn’t travel well via text, without background info on who you are dealing with.


Fair enough. I should probably use emojis more often.

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I’ve never understood all these comparisons of one cartridge over another.
Isn’t it far more important to hit the target where it counts?


That is logical thinking, I am going to have to ask to refrain from doing that.

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Yes, as long as adequate penetration is also present. Cheney shot a near octogenarian about the face/neck/ribs with birdshot and the man walked to the ambulance with little assistance. Nothing about his injuries PHYSICALLY stopped him from being capable of inflicting a mortal wound in return had he wished/been armed to do so. Such injuries from buckshot would have likely proved fatal rather quickly.

The issue, and something Doc G.K.R. has stated many times in his writing based on a whole lot of research, (I’m paraphrasing)is that pistol rounds regardless of caliber generally suck as man stoppers. That is why capacity trumps caliber when relying on them. Five hits with a .45 in the same spots as five hits from a 9mm or even .380 will have no discernible difference in effectiveness. Add in the stress of a life or death situation, the dynamics of such a situation(moving target) and the odds of landing that perfect ‘1 shot stop’ go out the window unless luck is involved or the person has a very low pain threshold. That is the key difference between a physiological stop and a psychological one mentioned in the article from P&S.

When asked on one of P&S’s live chats Doc G.K.R. stated, ideally, he would lean towards a shotgun loaded with some form of buckshot for self defense. Such a load would increase both the odds of central nervous system damage(cut the control wires) through penetration AND cause more rapid blood loss(starve the engine) through multiple wounds delivered at the same time. He has however also stated, as I have before on many threads here and elsewhere, that such a load also carries greater risk of overpenetration with regard to common building materials(I won’t even go into the lower capacity, greater recoil and slower reloads).

Intermediate rifle rounds can not only assure effective penetration of a ‘bad guy’, but due to their velocity and bullet construction can be designed to reduce overpenetration risks of barriers. Despite claims by some handgun ammo makers, achieving both within the velocity limits of common handgun rounds isn’t really possible at this time. Intermediate rifle rounds also have a second advantage over both pistol rounds and shot in that they travel at such speeds so as to be capable of damaging surrounding tissue(call it hydrostatic shock if you like though I’m told that isn’t the proper term) regardless of fragmentation or expansion. That secondary tissue damage, again, increases the rate of blood loss and the odds of a rapid physiological stop. A physiological stop is the ONLY type you can engineer/plan for(see the I linked article above).


If your using the same ammo wouldnt the .45 acp still make a slightly bigger hole and put a bit more energy in the target?


I mean I get what you’re saying in terms of the capacity advantages of 9mm though.

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Marginally. It really comes down to whether or not that <3mm would make a difference in hitting arteries/CNS components(you can NEVER rely on handgun rounds to expand real world). I wouldn’t bet on it. As to it allowing a faster ‘bleed out’, also not likely in any measurable way. The human body responds to ‘penetrations’ by constricting tissue around the wound to stave off bleeding whenever possible. Large wounds(significantly bigger than .45inch, think spear or broadhead arrow) reduce the body’s ability to do so effectively. High velocity rifle rounds also have that effect as the energy imparted on impact tears significant tissue surrounding the entry.

Temporary wound cavities from handgun rounds as seen above are really only a thing in gel. From my reading on terminal ballistics the temporary cavity, which appears more ‘shocking’ early in the .45 example, wouldn’t happen due to the elasticity of human tissue and certainly not to the extent visible in gel. Remember, gel is not equal to tissue it is only a standard ‘analogous’ to tissue allowing for a consistent baseline of measurement. For the most part handgun rounds poke straight(ish) holes and the more of them the better your odds of making someone stop doing what you don’t want them to do.


the thing is pistol bullets push through the body and the common fault is equating the human body to a solid mass of gelatin. A supersonic bullet has a preceding shock wave that will transmit hydraulic energy through a liquid media ahead of the bullet where a subsonic just pushes stuff aside (and the body has a lot of liquid and or empty space). The venous/arterial make up is quite strong and flexible and even with a direct hit (ball) just gets pushed aside, hence the reason for the expanding with sharp petal bullet (to lacerate).


Yeah, I thought I kinda covered that. I should note it takes a bit more than just being supersonic. 9mm travels above the speed of sound but not nearly enough to cause ‘hydrostatic shock’. Generally it will require a round traveling double that speed or more.

The issue there, which I did address, is that you can never rely on handgun rounds to expand ‘real world’ like they do in testing. Many a JHP, that never even remotely expanded, have been pulled from people that were shot. There are too many factors(clothing/body composition/striking bone or not) that can effect how a projectile will react to hitting tissue. Within the limited operating parameters of pistol rounds(velocity/weight/bullet construction) drastic changes are required to reliably improve a single desired effect. Those drastic changes and improved performance in one aspect are often at the expense of others.

There is a lot more wiggle room to adjust velocity of carbine rounds for example, and therefore even small changes in weight or bullet construction can be used to more reliably achieve the wanted results without sacrificing other positive aspects. Regardless of bullet weight or construction, a carbine/rifle round traveling 2500fps WILL impart that additional damage from hydraulic pressure. That leaves other design criteria open to be fiddled with so as to control penetration of soft tissue and reduce overpenetration of barriers(or even improve penetration of barriers if that is desired).

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  • 9mm pros

  • .45 acp pros
    Makes a bigger hole.

Recoil/ controlability is generally better with the 9mm although my 1911 felt like it kicked less than my Glock 19 so platform does make a difference, imo.

Having said all this the real question is why are old prehistoric dinosaur rounds being debated so much? Why are they still the goto?
Nostalgia and NATO should not be the deciding factor. There are superior modern rounds available to us such as the .357 Sig and 10mm.

But I digress , Lets go another 100 years arguing about which dinosaur ruled the Mesozoic era.

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.357 Sig has little advantage over 9mm in a self defense context and a few disadvantages. Reputable ammo manufacturers err towards building loads to meet the IWBA/FBI standards. A factory .357 Sig loading is generally throwing the same diameter/weight projectile as a 9mm at slightly higher velocities and will most often produce relatively equal penetration. The small velocity advantage MIGHT allow for better control of expansion, and that is certainly a marketing point for manufacturers, but it comes at the cost of snappier recoil and lower capacity in equivalent size handguns. Now if we were talking .357 Sig vs .40 S&W and ammo cost wasn’t an issue??? My vote would go to the Sig.

I will say that .357 Sig, using solid copper bullets out of a carbine with an appropriate twist rate, has the potential to be a GREAT hog round. The 10mm in its original FBI loading, roughly equal to lower power .41 Magnum, would also fair well in that regard.

Yes, a thousand times yes, both cartridges COULD be loaded hotter and provide more velocity/penetration/energy either through faster powders or ‘light for caliber’ bullets. But again, manufacturers aren’t going to do so under most circumstances because it would probably push those loadings beyond the IWBA/FBI standards I mentioned earlier. There are even rounds marketed toward handgun hunters that far exceed the velocity/penetration/energy of the same manufacturers ‘defensive rounds’. Extra penetration isn’t necessarily a good thing, and in fact may be a liability in a defensive situation.

Going down the ‘necked pistol cartridge’ rabbit hole, rounds such as the .22TCM and even the .32NAA have shown potential for lower recoiling rounds that still meet accepted ‘defensive ammo’ penetration requirements. I would like to see .22TCM with a bit heavier bullet but the only way to create such a load(short of depleted uranium) would be a longer bullet and the round already requires a .45ACP frame size due to its length.

To be clear, I am NOT advocating .22TCM/.32NAA or similar ‘wildcat’ rounds for self defense. Simply I think that direction, lightweight/low recoil/high velocity rounds that can reliably meet accepted standards, is what will carry development of defensive handgun rounds forward.


I don’t want to be hit with 9mm NATO or 115 HST without a plate. I will concede that point. Actually, I don’t want to be hit with a plate either.


Shot placement, shot placement, shot placement. That’s it… know what your round will do, learn were to put it based on that, then work until you have near perfect shot placement under nightmare situations.
THAT is the ONLY caliber discussion I will get into anymore.

I have treated gunshot wounds that should have been fatal except for a few centimeters and fought to control arterial bleeds from a pin sized hole.
Its all in were you put it.


On the first part, 1000X yes. A .22 in the heart will be more effective than a .45 ‘man stopper’ in the shoulder.

On the second, ONLY if the projectile can reach those arteries does it matter. Frank Serpico was shot in the face at contact distance with a .22(that lodged in his jaw) and still managed to return fire. And yes I will concede that even 9mm might not make it through a skull, but there is zero evidence a common(again, leaving out specialty loads like Buffalo Bore hunting rounds) .45 round would fare better.

People have questioned, here/other gun forums/on Quora, why I argue so stridently on the point that high velocity/intermediate rifle rounds are(in my opinion) best suited for personal defense. The science, from ability to incapacitate quickly to the(with proper ammo) reduced risk to bystanders, simply backs it up. Barring the ability to carry a carbine everywhere(To again quote P. Gomez “Last time I walked into a bank with an AK slung on my back they got nervous”), I’ll take a 9mm any day and keep my suppressed .223 ‘pistol’ within arms reach at home. More capacity with a 9mm means more chances to ACTUALLY hit something that makes a difference before I have to take my gun apart to get back in the fight. Better GUARANTEED penetration and accuracy from the .223 means less rounds needed.


That is a shot placement argument yet again.