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wrinkles
04-20-09, 17:52
Is anybody familiar with this book? This doesn't sound like anything I've read regarding FMJ and HP terminal ballistics.

Link to this thread. The post I'm quoting from is #22

http://www.xdtalk.com/forums/xdtalk-chatter-box/115181-not-picture-brain-bullet-went-through-3.html



Spitz And Fisher's Medicolegal Investigation Of Death Guidelines For The Application Of Pathology To Crime Investigation

This book is big, expensive ($150), and technical but it is THE BIBLE for forensic pathology. period. It talks about a lot more than gunshots as causes of death but if you read that chapter it would be more than you ever want to know. By far has the best pictures but beware they are extremely graphic!

OK, so anyways I don't want to ramble on and on about a bunch of stuff that no one cares about so I will keep it short and if you have any specific questions just post them up and I will try my best to give you an informed answer.

Some points that I learned that I think are interesting:

1. FMJ vs. HP: according to Di Maio there is NO significant difference in lethality. Even when HP expand fully the damage they cause is essentially equivalent. One can argue that if a FMJ exits the body less energy was transferred to the body, but this does not seem to be significant enough to make a measurable difference in the realistic endpoint (aka mortality). In their eyes, the real benefit to using HP as SD rounds is that they penetrate less deeply and thus have a higher tendency to stay within the body. This decreases the chance of someone else getting harmed.

Marcus L.
04-20-09, 19:44
Part of my job as a Federal LEO is also to be trained as a medic. The literature from the general medical community is actually not very advanced in ballistics science. Most of them equate wound trauma to bullet velocity instead of wounding mechanics. I have yet to read a civilian gunshot wound text book that gets it right. None of them mention Dr. Fackler.

Dr. Fackler spent the greater part of his life specifically analyzing handgun, rifle, and shotgun wounds. His conclusions were that wounding in handguns is dependent on direct contact with the projectile. The projectile must also generate significant shearing forces in order to more effectively tear the tissues it comes into contact with.

Take for example a pointed target arrow. If you've ever shot an animal with one, you'll notice that the tissues of the animal stretch around the arrow to allow it to pass with only a small level of actual tissue tearing and crushing. Pull the arrow out, and the tissues almost return to true since the tissues are so elastic. Pointed, or round nosed projectiles have a tendancy to push tissue out of the way instead of crushing it and tearing it. Here's a little exersize for you:

-Get a pine 2x4 board, two nails, and a hammer. Gently flatten the tip of one nail with the hammer so that it has a flat point. Hammer each nail into the 2x4 approximately 2" from the end. The pointed nail causes the board to split, while the flattened nail does not. This is because the flat point crushes more of the board as it penetrates instead of pushing it aside. Wadcutters, semiwadcutters, and JHPs have been observed to much more rapidly incapacitate animals during hunting for over a century than just using round nosed loads. These loads cause more crushing along their flattened frontal area, and their leading edges catch tissue.

Another advantage of some of the newer JHP designs like the Ranger Talon and HST is that they have sharp edges after expansion. This not only gives the bullet a flat frontal area for crushing, but the leading edges catch on and tear tissue more easily than standard JHP. Some JHPs like Silver Tips have smooth mushrooms with no sharp leading edges. Dr. Lane and Dr. Fackler wrote about this in the early 1990s with the Black Talon and how its leading edges caused more observed cutting and tearing in the outter edges of the permanent wound cavity on gun shot wounds.

The is really no credible ballistics researcher that will tell you the generic FMJ ammunition is just as effective as a good JHP design.

Pasteur
04-20-09, 20:08
The is really no credible ballistics researcher that will tell you the generic FMJ ammunition is just as effective as a good JHP design.

This is a tautology because no current researcher who would tell you that generic FMJ is as effective as a good JHP design would be considered credible.

However, the authors deserve a break, because the book was written in 1993 and the quote from Di Miao is even older. When the claim was originally written, a lot of Fackler's work on handgun bullet effectiveness had not yet been published. Also keep in mind, that in the 1980's the "good" JHP bullets were considered to be choices like the 147 grain Winchester JHP in 9mm, which had considerably less wounding potential than the better 9mm hollow points today. Finally, condsider that forensic pathologists are more concerned with lethality (whether the person dies) than bullet effectiveness (rapid incapacitation). It's not a huge error to say that the path the bullet takes through the body matters much more to eventual lethality than the difference between a 147 grain Winchester JHP from the 1980s and a 9mm FMJ.

DrJSW
04-22-09, 23:23
... the path the bullet takes through the body matters much more to eventual lethality than the difference between a 147 grain Winchester JHP from the 1980s and a 9mm FMJ.

Correct, Dr. Courtney. The primary means of incapacitation of a violent subject by penetrating missiles fired from a handgun is the path the bullet takes and the structures it directly bores holes through. Brilliant analysis, sir.

And yes, pathologists such as Dr. DiMaio, whose patients are all dead, have a different perspective than emergentologists like myself, or trauma surgeons like Dr. Fackler, whose patients are all alive (or at least start out that way). This does tend to skew the observations somewhat.

maximus83
04-25-09, 12:03
I would like to hear more on this discussion. My impression has been that, whatever the case may have been with ammunition from the pre-Fackler research era, TODAY you could safely conclude that modern JHP pistol ammo is more effective at rapid incapacitation than FMJ. And that is primarily because, with the improvements in ammo design, the modern JHP tends to both penetrate reliably, and expand in a high % of cases. I'm talking of course about PROVEN jhp ammo, that has been tested and established by ballistics tests, field use, etc.

In other words, if I use a quality JHP load in 9mm (say, the Federal 124gr HST), that is going to be significantly more effective in most cases than any FMJ out there, correct?

Marcus L.
04-25-09, 12:21
I would like to hear more on this discussion. My impression has been that, whatever the case may have been with ammunition from the pre-Fackler research era, TODAY you could safely conclude that modern JHP pistol ammo is more effective at rapid incapacitation than FMJ. And that is primarily because, with the improvements in ammo design, the modern JHP tends to both penetrate reliably, and expand in a high % of cases. I'm talking of course about PROVEN jhp ammo, that has been tested and established by ballistics tests, field use, etc.

Have you read any of the classic literature on the subject? The more you read, the more things fall into place for you and you get questions answered that you never knew were there. A good start is to get MacPherson's book "Bullet Penetration":

http://www.firearmstactical.com/bulletpenetration.htm

It is out of print, so you'll have to order it from Firearms Tactical. Mr. Dodson should be around to take your order. There's also a wealth of information on the Firearms Tactical website with summations of terminal effects information and links to cited works.

http://www.firearmstactical.com


In other words, if I use a quality JHP load in 9mm (say, the Federal 124gr HST), that is going to be significantly more effective in most cases than any FMJ out there, correct?

The short answer is that there is no FMJ loading that is as good as even a mediocre JHP design. Even if the JHP does not expand, it maintains a frontal semi-wadcutter cutting surface that does better at crushing and tearing tissue in the flight path. In terms of permanent crush cavity, even a slight deformation of the bullet will create a larger frontal area and thus more wounding ability. FMJ handgun bullets don't deform in the body unless they strike a large bone structure.

The only problem with using JHPs is that if the design isn't optimal, you can get too shallow of a penetration depth. However, if you use a heavy weight JHP in your given caliber, there is very little risk of this occuring. In general, penetration is never a problem with 9mm 124gr-147gr, .40S&W 165gr-180gr, and .45acp 200gr-230gr loads. Shallow penetration usually occurs in the lighter loads of the given calibers due to their reduced momentum and reduced sectional density. Such examples are 9mm under 124gr, .40S&W under 165gr, and .45acp under 200gr.

Gutshot John
04-25-09, 12:47
From my Paramedic/Corpsman training I was taught that velocity is a significant part of wound ballistics when dealing with high-velocity (supersonic) projectiles. While you can't compare pistol to rifle. A supersonic 147 grain 7.62x51 FMJ will do significantly more damage than a trans-sonic 147 grain 9x19mm JHP so yes velocity is important to wound ballistics. When comparing pistol rounds however differences in velocity are insignificant. More interesting comparisons are between standard and magnum cartridges. As has been pointed out, low velocity projectiles can do horrific damage but there are other forces involved in the wounding process i.e. the minie ball. The most significant process still seems to be the permanent cavity either by a single projectile or multiple fragments.

I'd be curious to know from DocJSW terminal differences between say a .22 Mag (of any kind) against a 9mm of similar design FMJ v. FMJ, JHP v. JHP. I've personally seen a .22 Mag do some significant damage, not that I'd ever advocate it,but it might be interesting for comparison's sake.

Generally speaking (though subject to multiple caveats) high-velocity cavitation will produce a temporary expansion of the wound cavity, this is significant only in solid (and to a lesser extent blood filled) organs like the liver. Hollow organs like the lungs will simply expand and then snap back. If you'd like to see this mechanism demonstrated, take some empty soda/beer cans and fill them with water. Shoot one with a 7.62 NATO and one with a 9mm and see which does more damage. Then do the same with an empty cans. Compare and contrast :)

It should be noted that many high-velocity rifle projectiles (even FMJ) will fragment in liquid environments due to the stresses/forces imparted onto the bullet by its velocity so it produces some pretty horrific permanent wounds by multiple fragments traveling at high velocity. Similar to an asteroid fragmenting when it hits the gravitational field of a planet.

maximus83
04-25-09, 14:40
Have you read any of the classic literature on the subject?

http://www.firearmstactical.com/bulletpenetration.htm



You're kidding. FirearmsTactical has BALLISTICS info available now? :)

Augusto
02-06-10, 11:40
On the other hand, DiMaio also says in the same book: "Wounds produced by the full metal-jacketed .30 Carbine bullet more closely resemble those from a Magnum handgun bullet than those from a centerfire rifle, whereas the wounds produced by soft-point or hollow-point ammunition are much too extensive to be ascribed to handgun cartrigdes and most closely resemble in severity those seen with a rifle. Thus, the .30 Carbine cartridge lies in a transition zone between rifle and handgun cartridges in terms of wounding. The constrution of the bullet loaded in the .30 Carbine cartridge case determines whether the wound is handgun-like or rifle-like."

This statement clearly says that there is a big difference between FMJ and HP. Maybe it´s inconsistent with the statement of the first post because the difference of velocity between carbine and handgun.

Augusto
02-06-10, 11:55
At http://www.firearmstactical.com/wbr.htm there is this headline:"DiMaio's Gunshot Wounds (First Edition): Does M1 carbine produce pistol type wounds with ball ammo and rifle-like wounds with soft-point or hollow-point ammo as DiMaio claims?" but I can´t access the full text. It´s in the Wound Ballistics Review Volume 5 Number 1, Spring 2001.

DocGKR
02-06-10, 17:56
Exerpts from, Fackler ML: "Questions and Comments". Wound Ballistics Review 5(1):4-6, Spring 2001.


"As for the 30-caliber M1 Carbine vs. M16 comparison, it depends on the thickness of the body part hit. Figure 1 illustrates the problem. About 15% of M16 bullets will act like the wound profile on top, and another 15% like the one on the bottom, with the average wound profile shown in the middle. If a bullet producing a profile like the bottom one penetrates an average human torso, it might well pass through from front to back without yawing—and cause less disruption than the M1 Carbine FMJ bullet over the same bullet path. But the average M16 ball round, at ranges under 100 yds (from a barrel of at least 20 inches), will yaw, break, and fragment in the torso, causing more damage than the M1 Carbine FMJ bullet. This inherent variability in the distance of penetration before yaw occurs is characteristic of all military FMJ ammo. It probably accounts for some of the wide variation in opinion on how much damage various military bullets cause.

Incidentally, some who have seen the M16 wound profile have suggested that it should be an ideal bullet for deer hunting. They point out that bullet should penetrate the shoulder muscles without yaw, thereby losing little of its wounding potential; then it yaws, breaks, and fragments at a depth that should be near the deer’s heart (from the side). Unfortunately, due to the inherent uncertainty illustrated in Figure 1, in about one in six shots the bullet would be likely to shoot through the deer without yawing significantly, and in another it would likely yaw too early, causing a lot of tissue disruption in the shoulder, but never reaching the heart. In contrast, the expanding bullet nearly always starts expanding within an inch of the skin, where its velocity is highest. This makes its effect far more certain and dependable than that of the FMJ bullet.

The major problem with trying to judge a bullet’s effectiveness by observing its effect on the living human, however, is that two bullets traveling at the same angle through a human torso can produce large differences in effect depending on which structures they hit. A 22 Long Rifle bullet that perforates the aorta will most likely have a far more effect than a 44 Magnum bullet that misses the aorta by 1/16 of an inch. Yet their paths would be essentially identical to anybody watching the shooting. Couple this uncertainty with the highly unpredictable psychological reactions of humans to being shot: some shot through the heart will continue firing and give no indication that they have been hit (for the first fifteen seconds at least—during which time they can shoot a lot of bullets), while others who have suffered a superficial graze wound might collapse immediately. These large causes for uncertainty, one anatomic, one physiological, essentially negate the concept of evaluating bullets by observing their effects in gunfights. When I first heard of the “one shot stop” concept, about fifteen years ago, it was immediately obvious that the human anatomy and psychological make-up would thwart the attempt. Then, when the “too good to be true” purported statistics began pouring in; it was again obvious what the authors had elected to do—make up “data” to fit their theory. Yes, it was nice that van Maanen’s simple mathematical comparisons finally proved the “one shot stop” data fabrication beyond a shadow of a doubt for the layman (those with scientific or statistical training had long since figured it out). But I remain amazed at the number of persons who had been taken in: perhaps this is what we should expect from a failing education system.

The problem of the anatomic uncertainty pointed out above has serious consequences for those whose lives depend on the effects of their bullets. How do they protect themselves from the fact that some bullets passing through the center of mass of the torso might just miss every vital structure? Keep shooting so long as the threat remains. One bullet might sneak through without hitting anything that bleeds a lot, but three or more greatly increase the chances of perforating something vital. Of course, the larger the expanded diameter of the bullet the greater the chance it will do the job. But this point can backfire if carried to extremes: bullet expansion decreases bullet penetration depth; and most vital structures lie deep in the torso. Ignoring this caused the unnecessary deaths of two FBI agents in the “Miami Shootout” in 1986. In summary, shoot enough bullets; shoot bullets that have enough penetration potential (12 inches in 10% ordnance gelatin); and shoot them in to the center of the upper part of the torso.

A particular bullet comes to mind, from the Diallo case, that illustrates these points. One of the 9 mm FMJ bullets, used by the New York City PD Officers, struck Amadou Diallo at the top to the curve of his aorta as it passed front-to-back. The bullet struck the aorta’s wall traveling in a path essentially parallel to it. That bullet sliced a one-and-one-half-inch hole in the wall of Mr. Diallo’s aorta. That same bullet then perforated his spine and divided his spinal cord. The criminal case was brought against the policemen because the city pathologist mistakenly thought that this particular shot, which everybody agrees caused his immediate collapse, was one of the first. Actually, the angles of the other shots proved it to be one of the last shots fired. Nobody could have planned that shot—it was a mater of luck. But the luck could not have happened without a bullet that had adequate penetration potential (coming from the front, the bullet had to pass through more than an inch of bone to get to the spinal cord).

In what you cited from DiMaio’s book, I find his “pistol type wounds” and ‘rifle-like wounds” imprecise and somewhat misleading. Would he call the first five inches of the average M16 wound (Fig 1) “pistol type” and the following five inches “rifle-like”? In the wound profile of the M1 Carbine firing a Remington soft-point bullet, the bullet expanded to 63 caliber, lost no weight in fragments, produced a temporary cavity five and one-half inches in diameter, and penetrated 17 inches. I have not done a wound profile of the M1 Carbine FMJ bullet, but would estimate a temporary cavity of three and one-half to four inches and a penetration depth of about 25 inches. The only thing I can do is to give you measurements from shots done under standardized conditions into standardized ordnance gelatin, which has been calibrated for penetration depth, against living muscle. Anybody who wishes to characterize these objective measurements as small, large, rifle-like, pistol type can feel free to do so, but I prefer to communicate such things using numbers wherever possible."

Augusto
02-06-10, 20:06
Thanks!