Bullet Effectiveness — what’s the big deal about 12″ penetration anyway?

In my ongoing quest to find the ideally suitable .380 round for a Taurus TCP, I’ve specified that I’d like the ammo to be able to meet the minimum 12″ penetration as specified by the FBI’s ammo testing protocol.

Needless to say, that’s generated some comments from various people, who want to know: Why?  Questions such as “Why do you need 12 inches?  The average bad guy isn’t even 12″ thick.” Or “Why do you need to follow the FBI protocol — you’re not the FBI.” Or “I don’t fancy myself some SWAT agent, so I don’t care what the FBI protocol is…”

Truth be told, I understand where they’re all coming from.  The most recent question was a simple one, in relation to one of my videos showing that the ammo would barely penetrate 10″, a person asked “why is 10 inches bad?”  I went on a writing rampage to try to explain it, and figured that instead of being buried as a forum post, it might make a decent article for the blog here.

Accordingly, here is what I might call…

A Beginner’s Guide to Ballistic Gel Testing Standards

In reference to the question “why is 10 inches of bullet penetration bad?” — It’s not that 10 inches is “bad” — in fact, I’d dare say that a lot of folks would be content with 10 inches, and that a bullet that penetrates 10″ of ballistic gel may possibly be an effective manstopper, under the right conditions.

But don’t confuse 10″ of gel penetration with 10 inches of torso thickness — they’re not intended to be the same thing!

Here’s the thing — some of the best minds in the business got together to evaluate handgun performance and come up with some standards that would result in repeatable, predictable, effective ammo performance.  A disastrous shootout in Miami resulted in calls to find out what went wrong, and how to prevent it occurring again.  The results are published in the FBI report “Handgun Wounding Factors and Effectiveness”.  You can read the entire report at www.firearmstactical.com, just google “Handgun Wounding Factors and Effectiveness“.

What is Ballistics Gelatin?
Ballistics gel is designed to mimic the properties of human tissue, and a bullet’s penetration in ballistics gel should be comparable to how the bullet would have penetrated through muscle tissue in a human being.  Ballistics gel is made from boiled-up animal tissue (hide, ligaments, tendons, etc) that is then distilled down to a powder (gelatin powder) and then mixed at a precise ratio and under precise conditions to result in a product (ballistic gel) that mimics the properties of flesh (to such forces as resistance, shear, stress, and tearing).  Mainly because it is flesh, just boiled and mixed together to make one big homogenous block.  It’s not exactly the same thing as flesh (you can easily tear off a chunk, for example) but as far as its response to a bullet, it is an excellent and highly accurate simulant.  It has been extensively correlated against actual shootings and wound examinations of trauma victims, and the penetration and expansion characteristics have been verified as being quite accurate to actual trauma wounds.

As said before, ballistics gel provides a tissue simulant that is homogenous (all consistent, all the same).  But humans aren’t homogenous.  We’re made of all sorts of different densities — lungs are basically empty, bones are comparatively dense, then there are super-stretchy tissues like intestines and not-stretchy tissues like the liver… we’re not homogenous.  So ballistic gel isn’t designed to exactly mimic the human BODY, it’s designed to mimic a relatively homogenous tissue such as muscle tissue.

“I’ve never been attacked by a block of Jell-O”…

I hear this a lot, from people who just don’t seem to understand — shooting into ballistic gel isn’t designed to mimic shooting into a human body.  Shooting into ballistic gel is designed to create a repeatable, standardized testing method that replicates the average performance of a bullet through a body, but does so in a way that is predictable, controlled, repeatable and directly comparable.  Because shooting into a body is one of the most unpredictable things we can do.  There are so many variables, it’s nearly impossible to account for them all!  Whether a bullet tumbles or not, whether it expands or not, whether it strikes a bone or not, whether it strikes that bone head-on and passes right through, or it strikes the side of a rib and is deflected; whether it strikes a critical organ or whether it sails straight through without hitting anything vital, whether it cuts an artery or only passes through a lung, and on and on and on… there’s no way to predict what will happen.

So we don’t try.  What we do, is we try to come up with a way of ranking the power of bullets through a homogenous medium of flesh.  I know people that get all bent out of shape about “jello shots” because “it’s not a body” but that’s not the point — what it is, is a way of saying “if you shot this bullet into muscle tissue, this is the results you’d get.”  And those results have been highly correlated against actual shooting victims.  And then you can directly compare the ballistics gel results from one bullet, to what you’d get with another bullet.  If one expands more and penetrates deeper, then you can unequivocally say “this bullet would produce more damage in a human body than that one, all other things being equal.”

Why Do I Want My Bullets To Be Capable Of 12″ (or more) Of Penetration?

So here’s a question that people seem to get confused over — does 10″ of ballistic gel penetration mean 10″ of penetration through a chest?  Not necessarily.  Maybe.  Maybe not.  It depends on the shot.  And it depends on the chest — if our attacker is a 105-pound waif supermodel, who is literally skin and bones, that 10″-gel-penetrating bullet might pass clean through her.  If we’re being attacked by a professional bodybuilder with a 52″ chest that’s all muscle, the bullet might stop well short of hitting his vitals.  If we’re being attacked by a 350-lb barbecue-and-gravy aficionado with a 52″ chest that’s all fat, the bullet might penetrate further through his chest than it would in the bodybuilder’s, but still stop well short of his vitals.  We don’t know what our actual shooting scenario will be, until we’re in it.

But what we DO know, is that if the bullet is able to go through 12″ of ballistic gel, it will also be able to punch through pretty much all of their chests and reach their vitals.  And that’s what counts.  Think of it as a relative power ranking, because, well, really, that’s what it is — a more powerful bullet could push through more inches of gel.  And, accordingly, no matter what tissue it hits in the body, it would be able to push through more of it, than a less-powerful bullet would be able to, if that less-powerful bullet were to have hit in exactly the same spot on a genetically-identical body.

So the penetration question is not about the chest thickness, it’s about however much tissue the bullet can penetrate through, regardless of what type of tissue it encounters (bone, lung, bowel, muscle, fat, etc).  The 12″ minimum takes account of factors such as having to shoot through bones, and at odd angles.  It’s all already factored in.

And bullet penetration is influenced by a number of design factors — the weight of the bullet, the type of bullet (a solid FMJ or an expanding hollowpoint), the speed of the bullet, the diameter (or caliber) of the bullet; all of these things have a direct influence on how deeply the bullet will penetrate.  Which is why we have to test.  And why we need a standardized testing medium to test in; one that will deliver consistent and comparable results.

The 12″ penetration figure the FBI arrived at is also a MINIMUM.  They would actually prefer to see about 14-15″.  The acceptable range for them is 12″ to 18″ of penetration; if it penetrates over 18″ then it would probably exit most bodies and therefore be not as efficient in delivering a wound, and also pose a threat to whatever/whoever is behind the target.  If it penetrates less than 12″, then it may not possess enough energy to reach the vital organs and cause an immediate incapacitation of the target.

What Stops An Attacker?

Now, keep in mind — an 8″-penetrating bullet may hurt like hell, it may cause a lot of bleeding, it may make the person who got shot drop their weapon and say “no more!”  That all may happen.  But it may not.  The target may be feeling no pain, they may be on drugs or feeling so much adrenaline that they don’t actually recognize that they’ve been shot, they may continue attacking even after having been shot.  That 8″ bullet may actually kill them eventually, too, through aggregated blood loss or through infection or any number of reasons.  But when talking about having to shoot in self defense, we’re not trying to kill our attacker, we’re trying to STOP our attacker — immediately.  And the only way to force a quick stop is to either hit the central nervous system (brain/upper spine) or damage the circulatory system such that it causes a rapid bleed-out and thus loss of blood pressure, which will deprive the brain of oxygen and cause them to fall unconscious.  That’s the goal — stop the attacker from continuing their attack.  We’re not trying to “kill” someone, we’re trying to stop them from killing us.

An attacker will stop for several reasons that are completely voluntary: sometimes just seeing a gun in your hand would cause an attacker to stop.  Sometimes seeing a gun pointed at them would cause them to stop.  Sometimes feeling the pain of a bullet hitting them would cause them to stop immediately.  Sometimes they may experience a psychological shock upon being hit, that causes them to drop to the ground.  But all of those rely on the attacker WANTING to stop, or choosing to stop.  And, frankly, sometimes they don’t want to stop, sometimes they choose not to stop, and you may have to force them to stop.  The only way to force them to stop is to take away their ability to attack — either through a central nervous system hit, or through rendering them unconscious (or dead.)  This is called an “incapacitating” hit — it’s when you take away their capacity to attack, so that they have no more capability of attacking.

Any type of bullet could cause any of the voluntary reasons to stop.  A tiny little .22LR or .25 ACP is just as capable of causing pain and fear and psychological shock as a .45 ACP.  Any gun is better than no gun, and many guns can provide enough incentive to get an attacker to choose to stop.  But in order to FORCE them to stop, you need to have the capability of rendering an incapacitating shot.

If you are relying on your weapon to render them unconscious/unable to move (or dead), then you need a bullet that can penetrate deeply enough to hit those vital organs and force their physiology to shut down.  The FBI testing came to the conclusions that a bullet needed the ability to penetrate through 12″ of gel in order to have the minimum amount of power necessary to (with proper placement) force the attacker to stop attacking.  And that penetrating 18″ or more was undesirable too.  It’s not about “the most penetration”, it’s about “enough penetration to hit the vital organs”.

Obstacles And Barriers
Here’s a key thing that many people don’t seem to factor in — you won’t always have a clean shot at the attacker’s chest.  In fact, you frequently won’t have that clean shot.  There will or may be barriers in the way.  I don’t know how many times I’ve seen video of attackers and defenders just standing facing each other, pointed at each other in classic Isosceles stances, trading chest shots, but I don’t think it’s too frequent!  The most common barriers you’ll encounter are clothing, and other limbs.  For example — if the attacker decides to shoot at you sideways, you may find yourself having to shoot through their arm or shoulder to even get to their chest — and that arm might be three or four inches thick or even more.  Or, a more likely scenario, what if you and the attacker are pointing guns at each other — in order to hit his chest, you may very well have to shoot through his forearm.  At an angle.  So the bullet might have to penetrate the outer layer of skin, traverse five or six inches diagonally through a forearm, and then push through the inside layer of forearm skin before it can even get to his chest.  That’s going to eat up a tremendous amount of the bullet’s energy; by the time it hits his chest it will already be expanded, and have lost much of its energy, and may not have enough power left to penetrate very deeply at all.  It’ll cause pain, sure, but the odds against it causing an incapacitating hit are much lower.  You’d need a really powerful bullet to be able to remain effective after encountering such a barrier — a bullet that would probably be able to travel through 14″-15″ of ballistic gel.

Now, law enforcement officers will face barriers that the general public aren’t as likely to; law enforcement officers may need to shoot through windows, windshields, car doors, etc., and so they need ammunition that they can count on that can overcome those barriers (and that’s why the FBI ammo test protocols include testing against bare gelatin, against “heavily clothed” gelatin, against windshields, and other barriers).  I would argue that in a personal defense scenario, we are not as likely to encounter such situations.  If there are substantial barriers between us and our attacker, that’s something you’re going to have to consider in the overall context of “are you in immediate danger of suffering severe injury or death” (or whatever your particular State’s legal standard is before the use of deadly force is justified).  In a standard mugging scenario, none of these barriers will likely apply, but in a carjacking situation, it’s possible that they may.

The point of all this is — you don’t know what your shooting scenario is going to be, other than that we can all pretty much assume it’s not going to be textbook perfect!  It’s very unlikely that if you’re involved in a defensive shooting, that you’ll be standing with a two-handed isosceles grip pointed at a defender who’s perfectly open to you, like a silhouette target.  You’ll be moving, they’ll be moving, there’ll be arms and clothing in the way, and you don’t know what angle you may hit the target at.  You may be on the ground shooting up, you may be turned at odd angles to each other, you just can’t predict what the scenario will be.

In order to account for all those variables, and to make sure that the bullet would have enough energy to do its job in any of the reasonably foreseeable scenarios, the FBI conducted tests and determined that 12″ of gel penetration would be the minimum power level their ammunition should deliver.
Is 12″ the minimum penetration standard you should consider?  That’s a personal decision, only you can decide what you’re comfortable with, but as for me and those I consult with, we feel that the 12″ minimum is a reasonable standard and one that would be a good starting point for anyone to carefully consider.  I would not want to rely on a pistol/ammo combination that can’t deliver 12″ of penetration.  I know that sometimes we may have to compromise, but my preference would be for a defensive round that can meet the FBI minimum of 12″ of penetration through ballistics gel.

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32 thoughts on “Bullet Effectiveness — what’s the big deal about 12″ penetration anyway?

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  4. Frank Chisowsky

    Hi ShootingTheBull,

    Firstly, I would like to say that this is an awesome blog. You probably addressed this elsewhere in the forum you mentioned or in another blog post etc, but I had a question regarding RIP effectiveness. I would first like to state that I am not hopelessly infatuated with the RIP projectile, but intrigued by it. Do these trocars induce damage above and beyond any other ammunition designed to fragment (even if it is shallow)? Does it create a larger temporary cavity due to its design? I am not a terminal ballistics expert, but it is covered briefly in certain military training evolutions and I immediately recalled concepts that were discussed when conducting “non-standard response” drills. Please inform me of any of these are ignorant of reality.

    The concepts in question suggested that the 5.56 is appreciated thanks to its tumbling rather than in spite of it, that different shots placed farther apart induce more damage than shots placed closer together, and that the temporary cavity displaced organs and caused shock greater than that of the permanent cavity. In theory (as nothing more than an amateur gun enthusiast), I pictured the RIP creating a large temporary cavity that would cause greater physiological shock than a round with a smaller temporary cavity (which would need to strike something vital in order to cause immediate or rapid incapacitation). Additionally, I supposed the trocars would tumble and rupture otherwise untouched organs (other than through reverberations caused by the temporary cavity) creating an effect similar to that of multiple gunshot wounds.

    This is excessively long. I apologize for that. I do not wish for this to appear as a rebuttal or a fanboy defense of the newest tacticool tool on the market. I am simply a military member who happens to find terminal ballistics and emergent technology interesting and your blog leads me to believe you would be able to help me understand better. If you have the time, I would love to hear your thoughts on how these factors apply to the ballistics testing you wrote about above.

    Thanks for your time,
    Frank

    Reply
    1. Shooting The Bull

      Hi Frank,

      You certainly do raise interesting questions. I was also quite fascinated by the design because I wanted to answer those questions too.

      I don’t know that we have definitive answers, as there are a lot of factors to consider. The trocars themselves, for example, penetrate about 4″ deep into ballistic gel, and weigh about 6 grains. How damaging is that? Well, consider that a steel BB that we use for calibrating gel will penetrate about 3.5″, and weighs 5.3 grains. So the trocars have a little bit more weight, and a little bit more penetration, than a BB. On the surface it sounds pretty comparable, and a BB at 590 fps won’t even likely break skin. However, the trocars are different in that they’re not “deployed” until the bullet has already broken skin.

      That’s one reason why, in my test on G2 R.I.P., I used a CCI .22LR segmenting hollowpoint bullet. It breaks up into three segments, each about 11 grains, and when fired from a pistol it travels at about the same speed as a G2 R.I.P. bullet does. And, like the R.I.P., it will not break apart and “deploy” its segments until it’s broken the skin and hit flesh, whereupon the hollowpoint cavity gets filled up and forces the bullet to break apart. So the relative damage of the CCI .22LR segmenting hollowpoint should be reasonably able to be considered against the trocars of the G2 R.I.P. And in that comparison, we still have a bit of a problem, in that the trocars weigh about half of what the segmenting hollowpoint fragments do. And, in comparison, the segmenting hollowpoint segments penetrate about twice as far as the trocars do. So the comparison seems to hold some validity — and in that context, we are left to wonder just how damaging those trocars would be to a human body, when they don’t penetrate half as far as the segments from a varmint round that’s designed for squirrel and rabbit hunting. So in that context I wouldn’t think that the trocars are going to be contributing any substantial wounding, and I would be very surprised if they could even make it past the ribcage, as a 6-grain projectile would likely not have enough momentum to be able to penetrate a bone. Seems like something I should find a way to test for though.

      As for the larger cavity — do the trocars create a larger cavity? Not in and of themselves; they create their own little wound paths, yes, but as far as the temporary cavity, what cavity they create is eclipsed by the main cavity caused by the cavitation effect of the base. If you look at the super-slow-mo shots in RatedRR’s video test, you can see that the trocars split off and make their own paths, but then the ultimate expansion of the main cavity eclipses them. The total temporary cavity created measures about 5.5″ in diameter. Now, it’s easy to think that they’re creating a bigger cavity because G2 Research has a highly misleading video on their site that shows what looks like a super-cavity, but that’s just deceptive marketing — in that video, they used a miniature gel block (it measures 4x4x9, instead of the standard 6x6x16, so it is literally 1/4 the size of a standard gel block). In their video the temporary cavity also measures 5.5″ in diameter, but it looks much bigger because of the smaller scale of the gel block.

      As far as fragmentation — 5.56 owes pretty much all of its wounding power to fragmentation, yes. Partly due to the Hague Convention which prevents the use of expanding ammo, military ammo needs to rely on other wounding mechanisms, and fragmentation gives a much bigger wounding path than a straight through-and-through such as would be done by a pistol FMJ. The 5.56 military rounds tumble and that additional drag force breaks them apart. When you combine that with the simply huge temporary cavity that the high velocity 5.56 round delivers, the fragmentation goes to shear the stretched flesh and massively magnifies the amount of damage done in the stretched cavity. If you think about a rubber band that’s been stretched to its limit, even a little pinprick can destabilize it and cause it to rip… that’s what’s happening with the 5.56. The temporary cavity is so huge that it stretches flesh to its absolute limits, and while it’s stretched so far it gets hit with dozens of tiny little fragments, and it causes tremendous permanent damage throughout the stretched tissue. That results in a gigantic permanent cavity of damage. In my testing, a .223 round like Lehigh Controlled Chaos delivers a permanent cavity of around 10″ long and 4″ in diameter. It’s truly spectacular and quite devastating. And yes, that goes to your point of wanting to space the shots further apart, because the .223 destroys so much tissue in such a large radius, that you don’t want to shoot into already-destroyed tissue; spacing the rounds out a bit will mean you will be hitting undamaged flesh and the net result should be a much larger degree of total destroyed tissue.

      Compared to the handgun round, it’s just not the same thing at all. You supposed the trocars would tumble; in my test shots I don’t believe that to be the case, as they seem to form a geometric circle where each trocar is pointing in the direction of travel. If they were able to reach the vital organs they’d be devastating indeed, but they stop penetrating so shallow that I would find it extremely hard to believe that they’d reach any vital organs. I don’t think they could penetrate any bone, so about the only way they could reach vitals would be if you were deploying it as a belly gun and shoving the gun up under the ribcage; in a case like that I do believe the G2 R.I.P. could be extremely damaging. Or a head shot — if the trocars deployed inside the skull, that would be devastating.

      But in a conventional torso shot, with the trocars only penetrating 3-4″, about the same depth as a BB does, I just can’t see how they would contribute much to the overall wounding and certainly they couldn’t do so to the vital organs. They do contribute to creating a larger damage pattern in the temporary cavity, in the same way as a 5.56 does but to a tremendously smaller degree. The initial permanent damage cavity left by a G2 R.I.P. is larger than that left by a conventional hollowpoint, but even then it only stretches about 4″. The trocars themselves penetrate to create a diameter of 3.5″, but the actual residual permanent damage cavity is only 2″ wide at its maximum point in the fragmentation cavity area. That means it’s half the diameter of a 5.56 round’s fragmentation damage. So for every inch of penetration, the 5.56 is damaging a volume of tissue that’s 4x as much as the handgun round. And, while the 5.56 is creating a 10″ long fragmentation cavity (meaning, the temporary stretch cavity that’s damaged by fragmenting particles), the G2 R.I.P. is making only a 4″ long cavity. Quick back-of-the-napkin calculations would show that a 4″ long x 2″ diameter cavity (as made by the R.I.P.) will destroy about 1/10 as much tissue as a 10″ long x 4″ diameter cavity (as made by the .223 PDX1).

      Now, to further complicate the comparison, you have to figure that the R.I.P.’s damage is going to be quite superficial, because its entire fragmentation cavity is done and finished by about 5″ into the gel block. Again, a steel BB will penetrate 3.5″, and the FBI and IWBA specifications for handgun performance dictate that a bullet needs to be able to penetrate at least 12″ through gel in order to be able to reach and disrupt the vital organs. So while the R.I.P. does create a lot bigger initial fragmentation cavity than a conventional handgun bullet, the question is — does it actually have any effect, other than to create a very nasty superficial flesh wound? A .223 or 5.56 will be creating that massive cavity as deep as 10″ or 11″ into the body, and the overall level of tissue disruption combined with the depth of tissue disruption makes the rifle round a devastating wounder.

      It seems like G2 Research was trying to create a handgun bullet that would wound in the same way as a rifle bullet would — and that would be a good thing, if it were possible. But the rifle has so much more energy at its disposal that it’s capable of doing damage in ways that a handgun bullet just can’t.

      Hope that all makes sense, and sorry for the encyclopedic length of the response!

      Reply
  5. David

    I ve been following your test o short barrel 9mm ammo. Firstly,I d like to piint out that Manufacturers callung Auto Pistol barrels 3″ and that includes the chamber-is misleading…a revolver barrel does not include the chamber so,it should be the same in auto pistols. The testing your doing would be more similiar to testing snub nosed .38 s.
    Your testing of the Speer Short Barrel ammo revealed your lack of understanding of Gun Powder Burn Rates-Speer used a much faster burning powder in this load to generate the same velocities as the +p ammo. The Short Barrel Gold Dot is my prefered load in my CZ75 Compact.
    During the 80s and early 90s I worked in the privatevsector doing Physical/Personal Security following stintvin the Military and a short career in Federal Law Enforcement. I ve been involved in seven shootings..one with .38 Spcl 158 gr +p lswchp=four shots,three hits,instant end to aggression.Two with .45 auto=185 gr Remington jhp four shots,four hits-ended up hitting him with pistol to stop him…second shoot with Speer 200 gr jhp-three shots,two hits,instant stop. Four shootings with 9mm=two with Federal Classic 115 gr jhp-in both of these guys absorbed multiple hits and ran away.one with .Winchester 115gr Silvertip-six hits before bad guy quit fighting and screamed for us to call him an ambulance. Last shootingvwas with Federal Hydra Shok 129gr +p..two shots ended aggression.
    My impressions in 9mm are that the 115gr rounds do not carry enough energy or,in the field,penetrate deep enough to stop a fight.The original loading of 9mm was a 124 grain bullet at around 1200 fps-any good modern design that hits that mark should do fine. The 147grain rounds wilk do ok but,basicalky,your loading down (not up) to make your 9 behave like a .38 spcl-for what??
    Good luck-and good work…and,please,note for the masses,that Factory Rated 3″ barrle on your auto pistol is really only 2″ after you deduct the chamber. FYI

    Reply
    1. Shooting The Bull

      Hi David,

      It is true that the revolver barrel doesn’t include the chamber in its measurement — but shotguns, rifles, and handguns all do. I would argue that, for ballistic purposes, it would be more consistent and more understandable if the revolver *did* include the chamber in the measurement. In terms of rifling, the barrel separate from the chamber is one thing, but in terms of ballistic performance, they should be considered together. If you view the barrel and chamber in terms of the overall space that the powder burns and the gases expand, the chamber is definitely included.

      You’re absolutely right that a 3″ semi-auto and a 2″ revolver will have basically equal ballistic performance (assuming that they’re chambered for the same round, and that the chamber in question has an overall length of approximately one inch). That’s one thing that makes it a little difficult to follow the BallisticsByTheInch.com statistics — they cut their barrels down and measure from the breechface to the crown, which is the way rifles/shotguns/pistols do, but they don’t account for the chamber when testing revolver cartridges. As such, when they report their velocities, they’re misleadingly low for the shorter barrel lengths, and you have to go to the “real world weapons” section to see how much better the results actually are, once you factor in the chamber length.

      As to this point:

      Your testing of the Speer Short Barrel ammo revealed your lack of understanding of Gun Powder Burn Rates-Speer used a much faster burning powder in this load to generate the same velocities as the +p ammo.

      I am quite aware of how burn rates of powder affect velocity and barrel lengths, but what I was pointing out was that the velocity between the +p and the “short barrel” +p ammo were nearly identical. And because the velocity was the same from a 3″ barrel, it seemed a reasonable assumption that there was, in fact, no difference in the powder. Remember, the short-barrel load is also “+p”. Your point would make more sense to me if the short-barrel load wasn’t +p…

      As to your shootings, my heavens, I wouldn’t wish that much activity on anyone! You’ve certainly had far more than your share!

      Reply
  6. David

    Reading my above post I noted numerous spelling errors-sorry.I was on my boat,in Galveston Bay,in the sunlight.
    I m sorry if I seemed to pick at you about burn rates,that was not my intention.
    Your correct about autopistols,shotguns,etc…includeing the chamber in barrel length,my point was to make people aware that 3″ is nt really 3″ in actuality.
    I carry the Gold Dot Short Barrel in my CZ75 Compact because,to me,it does not feel like a +p load-yet delivers velocities in the zone where I think they should be.
    The 80s was a crazy time for Law Enforcement-two of those shootings occurred while I worked in the States as a LEO-the balance were whike in the Private Sector-primarily in various locations in South America. And,in all honesty,each time,I was scared sh**less.
    Three most important things I can relate to anyone about a gunfight are this…
    1.Have a gun.
    2.Shot placement…a hit,any hit,beats a miss-a hit in the upper chest followed by a hit in the head is best.
    3.Dont quit shooting till your target quits moving or,you run out of ammo. If your target goes down and his feet are crossed,he s likely done-if not,reload and,shoot some more.
    I hope to never shoot another person again…but,I m willing-if need be.
    Keep up the good work.

    Reply
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  13. David

    S.O.B.-Personally,I m leary of the FBI/IWBA Standards..I think they focus too much on penetration. I agree a certain amount of penetration is needed to reach vital organs but,my opinion is,they exceed whats required and favor heavy bullets to achieve this. Heavy bullets sacrifice velocity. My observation is that you need a decent wieght bullet,niether the heaviest or,the lightest,with medium velocity.In 9mm,for instance,thatd be a 124gr grain at a minimum 1200fps..prefere closer to 1300fps personally.
    How about a test?? Forget assumptions..forget the FBI/IWBA standards.
    In the 70/80s the absolute best stopper known was the Remington SJHP (scalloped jacketed hollow point) 125gr .357 Magnum fired from a 4″ barrel revolver.
    Run this round (Federal-Winchester offer similiar versions almost as good) thru your testing-observe the temp cavity and penetration=compare it to the FBI/IWBA results…now,your dealing with the best stopper known in handgun circles…this should give you a Standard from a known performer to compare to.
    I understand your work is to find a good performer from a Pocket Pistol-still,haveing a baseline from a known street performer should prove illustrative. IMHO

    Reply
  14. Adam

    Hi,
    New fan of your YouTube channel and blog, love what you’re doing! I’ve recently become very interested in the subject of firearms ballistics (particularly handguns) and have been doing all kinds of reading and research. My brother and I were at the range a few weeks ago and we were wondering whether, for handguns chambered in either 9mm or .45 ACP, shots placed farther apart (in a 4″ grouping, let’s say) would be more effective and do more damage than shots placed in the same hole.

    Obviously, I’m not recommending aiming to do so, as I understand the difficulty of hitting the same exact spot on a great day at the range, let alone in the high stress of an actual shooting. I also understand that shot placement is really important and that the areas required to achieve forced stops are small, but I don’t know exactly how small, and knowing the damage done to tissue (and organs) around the bullet leads me to ask my question.

    I’d love to hear your answer, and once again I’m a big fan! You’ve helped me choose my defense ammo for my wife and I.

    Reply
  15. SHB

    Nice article…but the only thing I would like to comment on is your analogy of the 52 inch chest and why we need 12 inches of penetration. Well first of all, NO ONE’s chest is 52 inches deep. When you speak of chest size, it’s width not depth. A bodybuilders chest is not 52 inches deep and could not possibly be so. Neither that of an overweight man. Again – it is width. Which is in reality a circumference around the top of of your body. So using that analogy is misleading to those who do not understand the reason why we need 10-12 inches of penetration in the first place.

    The average male (non bodybuilder or obese man) is approx 12 inches to 15 inches wide (surface of chest to surface of the back). Now let’s add some thick clothing to the front (which doesn’t put up much resistance to a good round). Let’s be realistic here…no bodybuilder is breaking in to someone home. No obese person is breaking in to a home…we see more average size men, 150 to 180lbs, doing crime than those of larger physiques. So taking a man in between those lbs, whether or not he has thick clothing on, it WILL NOT take 10 to 12 inches to penetrate vital organs.

    The heart is not offset in the chest – the heart in fact is more centered of the body than anything. Not to mention, the most vital part of the heart is directly centered on the human body. So taking the FBI and other LEO out of the equations (which happen to have an extremely poor rate of well aimed shots), a person who is trained in self defense with a pistol KNOWS a well placed shot CENTER MASS on a BG will drop him/her…there is a significant less amount of tissue to penetrate hitting center mass of the chest. Getting through the breast plate is not a difficult task with ANY round. Whether you use FMJ or JHP (and that hp doesn’t fully expand), you will STILL hit vital organs.

    Anyone learning to defend themselves with a firearm is not trained to shot someone in the arm or leg or foot. You are taught to hit in vital spots of the body, center mass of the chest, pelvic area or if needed the head (which also is marked for vital head shot – hence the T box).

    I will end with this….a JHP round that penetrates 8, 7 or even 6 inches center mass will stop the heart.

    Reply
    1. Shooting The Bull

      ? A chest 52″ deep? Whoever implied or said that? I was talking about 52″ AROUND, in circumference, not in depth! Of course nobody’s chest is 52″ deep.

      Second, penetration through ballistics gel is not the same thing as penetration through a body, nor was it ever intended to be. The standards were achieved by taking known “good” bullets, ones that had consistently been very successful, and then firing them into gel to see how they’d perform. Knowing that “good” bullets that routinely were able to penetrate the chest, through the heart, etc, and adding in the potential of forearms or shoulders in the way, and firing those known good bullets in gel, the scientists determined that a bullet that penetrates 12″+ of gel is very likely going to be able to do the necessary job of damaging the attacker’s body.

      Third, you have to understand that it’s not entirely about penetration depth, it’s also about the bullet’s speed at that particular depth. A bullet that penetrates 6″ of ballistic gel, may not even make it TO a bad guy’s heart, much less make it THROUGH the bad guy’s heart. The last 4″ of bullet penetration has been shown to be about the same as what’s necessary to penetrate the exit layer of skin on the body. A BB from a BB gun will penetrate 4″ through ballistic gel, but won’t (generally) even break the skin of a living person. So saying that a bullet that penetrates 6″ of a body can stop the heart, yes, that’s probably true — but saying that a bullet that penetrates 6″ of ballistic gel will stop the heart? That’s not necessarily so, and contradicts the standards established by the experts in the field.

      Reply
      1. George Steele

        You make a very important point: measuring depth of penetration in gel is NOT meant to be an equivalency of penetration in flesh – it is a consistent analogue model for comparison of different rounds with one another. The depth of penetration in gel is meant to be used as an inference of what that same round would perform like – relative to other, known-effective rounds used in the field – when similarly used in the field.

        Even the notion of 12″-15″ penetration does not translate directly into effectiveness; it is, as well, a “figure of merit” that is used to determine relative effectiveness. No one would argue that a bullet that will penetrate through 15″ of gel will also penetrate over a 15″ path through a coat sleeve, arm muscle, upper arm bone, arm muscle, coat sleeve, coat body, rib cage, lung tissue, heart muscle – there are FAR too many indeterminate unknown obstructions in that path. It IS fair to say that a bullet that penetrates 6″ in gel will not get as far down that path as a bullet that penetrates 15″ in gel – i.e. the RELATIVE, rather than absolute performance is the issue being measured.

        I tend towards erring on the side of .45 ACP +P – not because I am a luddite, but rather because the round, fired from a 1911, established its street cred in battles around the world from 1911 to 1985 when it was replaced – although it is still issued, albeit not as the primary weapon. But the reasons for that replacement – magazine capacity, recoil, controllability by smaller people, compatibility with NATO logistics – are by no means to be interpreted as an indictment of the .45 ACP round, nor an endorsement of any “superiority” of 9mm. A round that proved itself over 74 years of military service to those whose only business was combat effectiveness simply cannot be sneezed at.

        But it is also fair to use gel tests as that same analogue when comparing, say, .45 ACP penetration to .40 S&W penetration in that same medium, and from there to infer their likely relative performance in the field. But it is an inference – not proof; the proof can only be determined after actual field performance is measured and assessed. Until that point, however, it is a valuable reference from which to make decisions about what ultimately could save your life.

        Excellent blog.

        Reply
  16. Jason N.

    First off, i love the science you put behind your reviews.
    You did reviews on the G2 RIP rounds. In the last video you spoke of true life shooting situations such as going through a wrist or forearm. Is there any way you could do a test with the rip rounds where you fire through, say plywood or ribs, set 6-8 inches infront of the ballistic gel? This should help with representing this true like situation.
    I am very excited to see if you will try this, and if you do, what the results will be.
    Thank you for all your videos.

    Reply
  17. John Swanson

    Just now getting around to reading this and I was glad David pointed out the “barrel length” issue between pistol and revolver. I had not actually considered that regarding my .357 LCR and 9mm P938. The .357 has a 1.875 inch barrel but about 3 inches including the cylinder chamber, so it sounds like a similar length to the SIG (3 inch “barrel” but about 2.25 inches after the breech). The operating pressures are similar, however the length of rifling is greater for the 9mm and the pressure loss at the gap between barrel and cylinder has to also adversely affect the muzzle velocity for the revolver. I still like my P938 best for many reasons.
    John

    Reply
  18. Greg Powell

    Thank you so much for your tedious and exemplary work on these ammo tests. I just purchased my Sig Sauer P938 Extreme and you’ve made my choice for defensive ammunition easier.
    I’m a subscriber to your channel and watch all the ammo videos pertaining to the caliber weapons I own. Again thank you for all you do.

    Reply
  19. Pingback: little choice for home defense

  20. Adam

    There must be much better materials for simulating bullet-behavior than government gel, because the FBI is basing their whole damn argument on the penetrating factor of that damn gel, so why cant someone think of something better????

    A dead pig! It would be gross to have to dig inside the dead flesh, and difficult to discern.

    i give up for now

    Reply
    1. Shooting The Bull

      Gel works. It’s been correlated against bullets in actual shootings. It does what needs to be done.

      Dead pigs are a lousy substitute, because dead flesh degrades extremely quickly. Furthermore, shooting a living being involves tremendous variability in terms of where the shot is placed and what type of tissue it hits. That’s not repeatable, and therefore the results cannot be scientifically verified. Gel is homogenous, it’s all one substance, all one texture, all one thickness, and as such is absolutely repeatable and scientifically verifiable.

      If you wanted to use animal flesh and restricted yourself to strictly considering muscle tissue, then yes that could prove useful, but you’d need to humanely euthanize the animal first, and then shoot the thickest solid-muscle area very quickly, within 5 minutes, maybe 15 minutes at most, before decomposition degraded the tissue and invalidated the test. This would be expensive, imprecise, and where are you going to get a supply of comparable animals of comparable size and such? Again, it’s not practical, and gel testing is far more accurate and scientific.

      Reply
    2. AnyMouse

      Many people are looking for a existing object that will simulate live human flesh, muscle, tissue. Dead animal parts can be fun to “experiment” with, but are not really exact substitutes. Given that only live humans are suitable test material, approximations are necessary. One can use dead animals as an approximation, but the results will be questionable. The reason for the “government gel” is that it is a realistic approximation that can be easily obtained, and it gives consistent testing medium for everyone wanting to analyze bullet wounds and tracks. The gel does not really simulate humans, but provides a medium for comparing different bullets. Dead animals and such are not uniform in construction, so results between one animal (or animal part) and the next cannot be predicted. There is other gel available, but the FBI standard has been accepted at the best available, to date. Water jugs, wet phone books, plastic cans filled with water, tires, roasted turkey and a whole menagerie of things have been used, but none adopted as a standard. The “government” gel is useful to test bullets from different manufacturers as it puts them all on the same playing field, with no fudging.

      Reply
  21. Brian

    Great blog. I’ve seen some of your other posts and would just like to pass one comment related to penetration… Not to say you haven’t addressed this somewhere, but I’ve not seen you discuss energy deposit vs. penetration/over-penetration. I don’t see more penetration as being necessarily a good thing. The more you penetrate, the greater the risk of pass-through. Any velocity the bullet carries out of the target is lost energy. Shooting to stop a threat, particularly someone on drugs is just as much about knocking them down or off balance as it is about creating a mortal wound. You want to shock the target (make the gel block jump). I think most people would agree 6″ of penetration is inadiquate for a defensive round, but I think I would choose the fast 9mm 100gr Pow’R Ball you tested that deposits 380ft-lbs of energy in the first 11″ of a target (perhaps only 8″ of a torso?) than a slower 124gr that might only deposit 90% of its 340ft-lbs of energy before passing through. There are lots of good loads in between those two scenarios of course, but I’m not aware of any 9mm (for example) that can deliver that kind of energy, particularly from a short barrel. I’m using this scenario becuase most of us carry shorter barrels that often don’t deliver nearly the velocity/energy listed on the box and when forced to choose between a load that delivers 10-15% more penetration (and increased risk of energy robbing pass-through) and one that delivers 10-15% more energy, I would usually choose the latter. Just one person’s unsolicited thoughts/opinion. Thanks for your thoughtful work on the topic.

    Reply
  22. Timothy

    Dead animals definitely do not work ballistics gel has no bones nor does it have organ cavities nor does it imitate what happens when a projectile bounces off of either of those

    Point being neither or grade approximation and everyday people look for better things other than live beings

    in other words no one knows until that moment some people get shot in the head to the brain and live some people get shot in the foot and bleed out

    Reply

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