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July 18, 2013, 11:38 PM | #1 |
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Expansion vs Penetration
Accurately placed expansion bullets plus good penetration without over penetration would be ideal. I'm sure that's obvious but a difficult balance. In practical use, this is what usually happens;
(I'll define "vital" as a large artery, heart, spine or brain.) 1. The bullet expands and comes in contact with a vital. 2. The bullet expands and doesn't penetrate deep enough to come in contact with a vital. 3. The bullet doesn't expand and misses a vital due to the bullets smaller diameter. 4. The bullet doesn't expand and hits a vital due to accurate shot placement. 5. The bullet over penetrates and potentially causes collateral damage. To consistently achieve the above five possible outcomes, we would need the following: 1. For the first case; A mid to high powered cartridge (1000fps+), with excellent expansion design. 2. For the second case; A low to mid powered cartridge (1000fps-), with excellent expansion design. 3. For the third case; A mid powered cartridge (1000fps). 4. For the fourth case; The same as the third case. 5. For the fifth case; A mid to high powered cartridge (1000fps+). A mid powered hollow point could teeter between no expansion and under-penetration. A mid powered full metal jacket could teeter between missed vitals and over-penetration. It seems that a non-expanding bullet in a high powered cartridge would be the most reliable. Relying only on the shooters ability. Note: 1. FPS alone does not tell you how much damage will be caused but it can tell you if the bullet will expand. 2. A 124 grain FMJ 9mm fired from a barrel which delivers 1,000+ fps should provide adequate penetration to hit a vital with the chance of over penetration. |
July 19, 2013, 03:45 AM | #2 |
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Ooookay. Velocity is the only factor mentioned as to "power level" . Not that any of the following is the be all and end all , but bullet wt , and dia/ sectional density would flesh out a more complete model.
What is "excellent expansion" , "overpenetration" , and "underpenetration" ? I have my views , but knowledegable individuals have been hotly debating all those , and a lot more since at least the era that Lee Jaruas sold the first commercially succuesful line of reliably expanding ammo.. (FWIW I am of the thought that there are more than one aproach to ammo design that works well in the real world , and results are more important than theoretical checklist .) Give any of the stated reasoning , I'm scratching my head how the leap was made that the prefered 9mm ammo was 124fmj @ a mild vel ? As controversial as 9mm ammo choices remain to this day , it would be a safe prediction that there would be a strong concensus than any of the top 10 selling major brand 124-127 jhp loads would be much better choice than fmj. |
July 19, 2013, 04:16 AM | #3 |
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I only use FMJ for target shooting, for SD I always carry HP ammunition.
In 9mm, I have been shooting 147 grain bullets more than 1000 fps for almost 20 years, lead, FMJ and HP. In the past many of them were +P loads, but now days with our current selection of powders, it's pretty easy to get a 147 grain bullet above 1000 fps. The possibility of over penetration should be assumed on ANY ammunition, I am a firm believer that thought should be put into what is behind the intended target, even in a SD situation. Much of my training advocates this as well.
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July 19, 2013, 09:00 AM | #4 |
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Expansion vs Penetration
In many, if not most, cases, penetration > expansion.
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July 19, 2013, 11:18 AM | #5 |
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I saw an xray of a man who had been shot with two 45 caliber bullets. The bullets were hollow point and they had expanded. One of the bullets penetrated a lung and the other bullet did not make it past the sternum. I'm not convinced by the results of ballistic gelatin tests.
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July 19, 2013, 01:31 PM | #6 | |
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Quote:
When it comes to SD/HD, accuracy and reliability trumps penetration and expansion everytime. Most times the size of the hole in the BGs heart/brain will have little to do with how fast he dies. How does a hole made by a .45 FMJ in a person's lung any different than one made by a nicely expanding 9mm? Expecting a expanding bullet to compensate for a near miss to a vital organ is foolishness. That's not what they're about. Over-penetration is more a factor of caliber than bullet type, and missing the target all together means one has a better chance of harming someone else beside the BG they're shootin' at. |
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July 19, 2013, 02:50 PM | #7 | |
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And the example you listed is why I am not convinced that HP's are the end all self defense bullet type. I'd much rather have pass-throughs with little to no expansion than any bullet stopping at the sternum, or not being able to pass though the skull, or another bone, while I am aiming at a vital organ. I don't care that pass-throughs are "wasted energy" I'd rather have that energy "wasted," than all dumped at once, where it can't even make it through the sternum. Now, if we were talking a high powered rifle, with enough energy to cause hydrostatic shot that will destroy organs, well that's a different story than measly pistol rounds. In that case, having all that energy dumped quickly could be beneficial. |
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July 19, 2013, 03:10 PM | #8 |
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KE level....
I've posted remarks in the past about how I think the KE or kinetic energy level of a handgun round is highly under-rated.
A fast, powerful round that feeds well & offers good marksmanship is what's ideal for a duty or protection round(caliber). The .357sig is a great example. The caliber was R&Ded by SIG Sauer engineers to replicate the .357magnum JHP out of a 2.5" revolver barrel. The KE level is higher than other defense loads; .380acp, 9x19mm, .40S&W, .38spl. Some LE officers & armed citizens gripe about the muzzle blast & recoil but those can be addressed with proper training. The little known .40Super caliber also had a high KE level & would have been a potent defense load but it never really caught on in the USA. |
July 19, 2013, 03:24 PM | #9 | |||||||
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"It is long been a principle of ours that one is no more armed because he has possession of a firearm than he is a musician because he owns a piano. There is no point in having a gun if you are not capable of using it skillfully." -- Jeff Cooper Last edited by Frank Ettin; July 19, 2013 at 04:10 PM. Reason: correct typo |
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July 19, 2013, 04:20 PM | #10 | |
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My Suburban at just over 2 MPH has 1000 ft-lb of kinetic energy. The bullet I shoot out of my 9mm only delivers 400 ft-lb. My personal bet is that someone hit with the 400 ft-lb of energy described above will stop what they're doing a lot quicker than someone hit with the 1000 ft-lb of energy described above. |
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July 19, 2013, 04:33 PM | #11 |
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I normally try to avoid referring to other people's perspectives on debated topics, but since Frank Ettin already broke the ice on Greg Ellifritz, here's an article that's somewhat interesting. Granted, it's more of a caliber caparison than a bullet comparison.
http://www.buckeyefirearms.org/handgun-stopping-power I don't know that this data is truly unbiased, however. The author says he only included results from criminal altercations or military battle. That right there will change the picture a lot. Are military combatants, who are trained and mentally prepared for fighting, going to as easy to stop as some petty thief who's breaking into homes looking for electronics? And what are these military combatants probably being shot with? I suspect that 9mm and .45 autos look worse in the results simply because they tend to be used when more determined combatants are involved. So even though the author says he has no dog in the fight, I don't believe any data, no matter how large the sample, can really paint the whole picture so long as the situations and variables are not controlled and identical. Nonetheless, it's still interesting to look at, even if the only real conclusion is, as Frank stated, "There are no magic bullets." Last edited by idek; July 19, 2013 at 04:56 PM. |
July 19, 2013, 04:34 PM | #12 |
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Energy, momentum, bullet construction, bullet area all come into play.
Energy is more a function of velocity than weight. It has more to do with destructive potential. Momentum is an even function of weight and velocity. It is a indicator of penetration. Bullet area is a function of size of the projectile and is an indicator of how large a crush cavity you will get. Bullet construction is a combination of material and design. It can be used for better penetration or enhanced destruction. It's very hard to get a bullet that is constructed to penetrate alot and yet do great damage. Any ammunition you get is a compromise. You can have high energy and low weight to enhance destructive capabilities or lower energy but more momentum (weight) for more penetration. But with good bullet construction you can get more penetration or destruction. And of course larger bullet area can be used to get more of each or both. If you want it all, real good penetration and real good energy and excellent bullet construction you need to go to some high velocity heavy weight big bores like .44 magnum DPX (ouch!) And that load demands a heavy big gun! Seriously folks, it is mighty hard to get one type of ammo that does it all. Mighty hard! Deaf
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July 19, 2013, 04:51 PM | #13 |
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Frank, it almost seems like this topic might have come up before as prepared as you were with your response.
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July 19, 2013, 05:25 PM | #14 | |
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"It is long been a principle of ours that one is no more armed because he has possession of a firearm than he is a musician because he owns a piano. There is no point in having a gun if you are not capable of using it skillfully." -- Jeff Cooper |
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July 19, 2013, 06:38 PM | #15 |
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Shoot fatter bullets, no need for expansion.
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July 19, 2013, 07:00 PM | #16 |
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Check out the Sept/Oct 2013 magazine "American Handgunner" article by Greg Ellifritz. The credentials for Greg is impressive and his data isn't just from the gels, it's from actual wounds. It basically supports what many have said, shot placement and especially the control of follow up shots count the most. The differences between 380, 9mm, 40 and 45 cal are not so separated as many may think. There were other points interesting in the read. The "chart" will surprise you and may change the thinking of some, especially the stats on the 380. The magazine had the chart but didn't see it on the url. Support the magazine and spend the 6 dollars for it. For quick look, http your way to americanhandgunner dot com/defensive-carry.
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July 19, 2013, 11:50 PM | #17 |
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Shock, stress, blood loss...
I say high KE rounds like the .357sig or .40S&W or 10mm have value because if you shoot at a human being the shock & impact of the entry wound be higher than a smaller, lower KE level round.
Blood loss, shock and trauma can cause a subject to stop fighting. Keep in mind that drugs or alcohol may also prevent a rapid reaction too. Even a .44spl, .45LC or .45acp rd may not stop a spun-out, hyper drug addict. Clyde |
July 19, 2013, 11:59 PM | #18 | |||
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Quote:
See post 9:
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July 20, 2013, 03:12 PM | #19 |
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All handguns are relatively poor "stoppers" regardless of caliber or bullet used. Shot placement and sufficient penetration are paramount, all else is secondary.
Expanding bullets? If you carry a load that's capable of sufficient penetration *and* expansion then the additional damage can only increase the bleedout rate that leads to incapacitation due to drop in blood pressure and oxygen deprivation to the brain. In general this is a good thing. However, there's no scientific way to prove if this expanded bullet will increase the bleedout rate enough (seconds? minutes? hours?) to alter the outcome of the encounter (doesn't do you much good if he passes out from bloodloss in the ambulance from JHP's instead of the ER from FMJ *after* planting daisies in your hair). I follow the conventional wisdom of carrying the most powerful caliber I can shoot both accurately and quickly w/quality expanding bullets (except for .380's where it's FMJ only as sufficient penetration trumps expansion every time) but don't believe that expanding bullets will significantly increase the chances of my hits ending the fight (YMMV). Tomac
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July 20, 2013, 05:10 PM | #20 | |
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There are a number of false premises in your original post. Start with this one.
Quote:
That, combined with your low post count, leads me to the following advice: Spend a year here reading a lot and posting a little. The occasional question, yes...but most questions have already been answered many times over (see Frank's post #14) and a search will help with that. |
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July 21, 2013, 09:28 AM | #21 |
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Penetration vs Expansion
Good morning folks,
Just joined TFL and find it very interesting. I'm a long time shooter, hunter, combat vet, hand loader. I've been on other forums and found some of them to be loaded with never-been-in-combat experts who are certain they will react positively in a SD situation with the associated huge adrenalin dump, tunnel vision, etc. Some people out there are really scary and not helping deflect the present anti-gun rhetoric. Some are "trollers" for sure but the internet and Youtube have created a lot of self-proclaimed experts. Some are very credible, some not so much. That said, the TFL forums I have visited so far are very good, very interesting and there appears to be a fair amount of courtesy for the opinion of others. In regards to the conversation concerning penetration vs expansion, I am certainly in agreement that one bullet cannot do it all and certain amount of penetration is required to stop a BG. Personally, for me, the bigger the handgun bullet the better and 12" to 15" of penetration with an expanding bullet (Critical Duty, HST, etc) is probably quite acceptable. I'm in favor of the big hole and a big "energy dump". After having been in the jungle, I've seen a person keep going after being hit in the torso. In many case, initial pain was not an issue because the high-power non-expanding rifle bullet zipped right through without the attendant organ shock of an expanding style hunting bullet that dumps a tremendous amount of energy before it exits. As mentioned above, the mere fact of knowing you've been shot is enough to stop many people...call it "psychological shock value". But the body seems to go into almost instant shock, numbing the initial pain, so hitting a vital organ causing massive blood loss (oxygen deprivation to the brain) is important and most vital torso organs are within a few inches of the skin so the bigger the hole, the more chance you have to induce massive blood loss...especially with multiple hits. I carry a G23 w/night sights and my house gun is a Taurus P1911 with a 4 1/2 lb trigger and night sights. I also have a Taurus 99 9MM and a Ruger MKII with a bull barrel. I practice with all of them with emphasis on the G23 and 1911. I'm not a bullseye shooter but I'm fairly decent at center-mass. I hope I never have to do a Zimmerman but I do practice turning the gun immediately upon clearing the holster and getting the first shot off from slightly above waist level just in case the BG is "right there" because, in my mind, that's the very worst case scenario...other than taking a hit. Anyway, just wanted to say "Hi" and my initial impression is this will be a fun informative forum. Jim |
July 21, 2013, 02:34 PM | #22 | |
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When you step back from all of that, and look for commonality between people with extensive street experience, scientists, enthusiasts, etc, the above points are almost unanimously present. We may agree or disagree on other specifics, but it should be accepted that the statements above are all true.
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July 21, 2013, 03:13 PM | #23 |
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Well said, RBid.
Tomac
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July 21, 2013, 04:09 PM | #24 | |||
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Quote:
Quote:
In the Ellifritz link I posted, his results showed 61% one-shot incapacitation with .22lr, 72% with .32 caliber cartridges, 62% with .380 ACP. Meanwhile, 9mm Luger and .45 ACP results show 47% and 51% one-shot incapacitation respectively. According to this particular study, even the "larger holes are better than smaller holes" statement would go out the window. Something seems wrong when .32 ACP/.32 Long looks like the clear winner in a comparison of handgun cartridges. If that means I'm "bashing" Ellifrizt's work, then I guess I'm bashing it. |
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July 21, 2013, 07:04 PM | #25 | |||
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First, look at the article and the chart there labeled "Failure to incapacitate." Then have another look at post 9 where I quote Ellifritz: Then also look at post 9 where I quote the FBI paper entitled "Handgun Wounding Factors and Effectiveness", by Urey W. Patrick, page 8: In other words, much, or even most, of the time a person when shot will choose to stop what he's doing for psychological reasons. He is not actually incapacitated, but rather he decides to stop because it hurts, or he's afraid, or he's convinced himself that once he's been shot he's incapable of continuing, etc. In such cases, what he's been shot with really doesn't matter. It's enough that he's been shot and he knows it. His mind then tells him not to continue, or his mind tells him he can't continue. His mind decides not to continue, even though he may in fact be physiologically capable of continuing. But what if the assailant's mind doesn't know or care that he's been shot? That certainly seems to happen at times. And in such cases, the assailant isn't going to stop unless/until his body is sufficiently damaged in such a way that he is forced to stop. So he might be forced to stop because his brain or spine is physically damaged. He might he might be forced to stop because major bones/skeletal structures are smashed to the point that he has lost mobility. He might be forced to stop because he has lost so much blood that the oxygen level in his brain has fallen to the extent that it can no longer function. The thing is that if you need to shoot someone in self defense you can't know ahead of time whether he will stop because of psychological factors or you will need to damage him enough to make him physiologically incapable to be a continued threat. Bullets making more and larger holes deep enough in the right places are more likely to produce a sufficient physiological response if the assailant is not willing to just stop because he's been shot.
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