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calvin118
05-04-09, 22:26
Hello all,

I am a physician (anesthesiologist) who works at a major metropolitan trauma center. I see a lot of gsw trauma, and although I do not directly perform the surgery it is my job to closely follow and respond to what is happening on the other side of the curtain. My experiences have raised a few questions that I wanted to share.

I have reviewed a lot of the ballistic gel data linked from this and other sites, yet am still a bit confused about the role that bone plays in the equation. Like many of you, I have read the Canadian govt study in which they placed porcine ribs in ballistic gelatin and the ribs did not seem to be much of an impediment. I have serious questions about their methodology, though. Old, presumably dry bones from dead animals have very different physical properties than living, hydrated bones.

DocGKR referenced a study by a Dr. Lane done in 1993 for the FBI. I could not find it myself, and thus have no understanding of the methods. I did, however, come away from DocGKR's statement under the impression that anything smaller than a .40 might not reliably pass through a porcine femur.

In my own limited experience, I have seen a number of xrays in which a femur, pelvis, or vertebral body *appeared* to have stopped what *appeared* to be (judging by the shape) a 9mm fmj bullet. On the other hand, I have seen the humerus, tibia, etc. shattered by projectiles that passed out the other end of the limb and into obscurity. Additionally, I have seen instances of bullets deflecting. Just last week a man attempted suicide with a .38. He shot himself slightly off midline at approximately a T6 level, and the bullet apparently ricocheted and traveled downwards through the abdomen and punctured several loops of bowel.

I have also heard and read a lot of *anecdotes* about 9mm and smaller rounds deflecting off bone (such as the rib in the Miami shootout).

To me, this seems like a huge x-factor. Has anything else been done to assess the effect of bone on terminal ballistics? Will a long bone reliably stop a 9mm, or was what I saw merely a small and biased sampling? Will the sternum or ribs of a large man reliably slow down or deflect smaller rounds? Is/was this only an issue with the older bullet designs weighing less than 124 grains and without +p? Is deflection all about the weight of the bullet, or is the shape important as well (e.g. is the short, blunt nosed .40 less likely to deflect at a less-than-head-on angle than the more conical 9mm at a similar weight)?Is the risk of deflection also present with windshields, heavy clothing, etc. etc. with less than perfectly head-on collisions? Is a differential response to bone a limitation of the gelatin model in comparing different calibers?

Thank you all in advance for your help,
-Calvin

Odd Job
05-06-09, 19:11
There is probably not enough data out there with regards to specific weights and calibres as regards bone fractures. However 9x19 is the most popular carry caliber by far in South Africa and it is what I have seen most often in the theatre recovery jars.

My take on this is that 9mm is just fine for breaking bones. A lot of smaller calibres have done it in unexpected circumstances also, the most noticeable of which was a .25 (or thereabouts) that went through a guy's hand and his thigh, fracturing the thumb and also the femur.

Sure, I have seen FMJs pancaked up against the femur, but I've also seen them go right through, with nary a concern for any bone in between (or apparently so).

But where we stand right now, I don't think we can answer your questions with actual shooting data because we can't get consistency in the data. We can't replicate the shots when comparing one calibre to another. The slightest difference in impact position or angle of incidence could mean that a whole different architecture of the bone is involved. That affects the likelihood of deflection and the amount of cortex that is potentially in the trajectory.

What about bone mineralisation differences, or miscellaneous pathologies that could affect the structure and density of the bone?

I'm am aware of some studies with bone simulant, but I haven't looked into those with enough care to come to an opinion whether they would have merit in answering your questions.

I must state for the record that I am not a doctor. I have X-rayed one or two fractured GSW patients, however.

tpd223
05-07-09, 12:02
In the shootings that I have seen I have not noted 9mms having any great difficulty in breaking bones. The biggest issue it would have is being typically loaded with a semi-pointed RNFMJ bullet.

DocGKR
05-08-09, 01:15
Dr. Lane compared 9mm 115 gr and 147 gr JHP with .45 ACP 230 gr JHP --the .45 ACP created greater bone damage and were more likely to punch through the swine femurs than the 9 mm's.

IIRC, no 9 mm shots were deflected by ribs during the 1986 FBI incident in Miami.

Lot's of handgun projectiles of all calibers, including .45 ACP, have deflected off various maxillofacial and cranial bony structures and failed to penetrate into the cranial vault during actual shooting incidents.

There is no good way to quantify bone, due to varying sizes, shapes, and densities of living bone, as well as variations in striking angles.

If you really need to shoot through bone, use at least a .44 Magnum or better yet a rifle cartridge or 12 ga Brenneke slug...

BBMW
04-04-10, 17:58
I'm dredging this up from the dead thread underworld because I was thinking along the same line, did a search and found this.

I had a follow on question for Doc, and anyone else, which is:

Would the fact that bone penetration/deflection is a issue, and it's something that isn't accounted for in gelatin testing, tend to be a modifying factor in any decisions about caliber and load selection based on gelatin testing. Given any level of rough equivalence between two rounds in gel testing, wouldn't you always want the heavier choice, given that weight seems to be a large factor in bone penetration?

For instance, if the choice is between a Glock 19 or glock 23, and you''d only be giving up two rounds for the ability to carry a significantly heavier bullet, would the bone penetration issue push toward the 23, all else being equal?

Dragon Slayer
04-04-10, 18:11
I'm dredging this up from the dead thread underworld because I was thinking along the same line, did a search and found this.

I had a follow on question for Doc, and anyone else, which is:

Would the fact that bone penetration/deflection is a issue, and it's something that isn't accounted for in gelatin testing, tend to be a modifying factor in any decisions about caliber and load selection based on gelatin testing. Given any level of rough equivalence between two rounds in gel testing, wouldn't you always want the heavier choice, given that weight seems to be a large factor in bone penetration?

For instance, if the choice is between a Glock 19 or glock 23, and you''d only be giving up two rounds for the ability to carry a significantly heavier bullet, would the bone penetration issue push toward the 23, all else being equal?

Or better yet a 45 ACP, that Doc GKR says is the better bone performer? But in reality if you do have more rounds in a 9mm would you shoot a few more with the intent that they do go different ways and are not affected by bones?

DocGKR
04-04-10, 23:05
"Given any level of rough equivalence between two rounds in gel testing, wouldn't you always want the heavier choice, given that weight seems to be a large factor in bone penetration?"

It is a factor, but so is bullet construction, velocity, weapon reliability, and "shootability".


"For instance, if the choice is between a Glock 19 or glock 23, and you''d only be giving up two rounds for the ability to carry a significantly heavier bullet, would the bone penetration issue push toward the 23, all else being equal?"

Well that is an easy one, I'd take the G19 because it is more reliable, durable, and easier to shoot. Terminal performance is only one factor; I would rather shoot a 100% reliable weapon using plain FMJ, than an 90% one with the latest high tech ammunition.

WS6
04-04-10, 23:05
Dr. Lane compared 9mm 115 gr and 147 gr JHP with .45 ACP 230 gr JHP --the .45 ACP created greater bone damage and were more likely to punch through the swine femurs than the 9 mm's.

IIRC, no 9 mm shots were deflected by ribs during the 1986 FBI incident in Miami.

Lot's of handgun projectiles of all calibers, including .45 ACP, have deflected off various maxillofacial and cranial bony structures and failed to penetrate into the cranial vault during actual shooting incidents.

There is no good way to quantify bone, due to varying sizes, shapes, and densities of living bone, as well as variations in striking angles.

If you really need to shoot through bone, use at least a .44 Magnum or better yet a rifle cartridge or 12 ga Brenneke slug...

I always figured that the more velocity and energy present, the better a projectile would do against a bone, with regard to deflection vs. penetration.

Never shot any large bones, but this seems to be the case regarding metal and wood. I know neither of these are bones, though.

DocGKR
04-04-10, 23:12
Bullets that do well against bone generally fare well against automobile windshield intermediate barriers.

WS6
04-04-10, 23:27
Bullets that do well against bone generally fare well against automobile windshield intermediate barriers.

Which would mean that they are all about equal using bonded rounds in 9/357/40/45, no?

I wish there was a way to get ahold of some deflection test #'s between those rounds and windshields. I know OP has done some, but I was wanting something like:

"XX load inches of deflection from point of aim 24" behind windshield at compound angles of XX* and XX*."

tpd223
04-04-10, 23:48
On all of the windshields I have shot deflection seemed to be quite random. One only gets trends, not absolutes, we are talking about a rather violent event, not billiard balls bouncing around a table at predictable angles.

Overall I have noted that the bigger bullets can tend to give less deflection, bonded bullets do a better job than non-bonded bullets (mostly but not always), even FMJ bullets can shed the jacket when going through windshields.

DocGKR
04-06-10, 10:35
"Which would mean that they are all about equal using bonded rounds in 9/357/40/45, no?"

Not exactly; there does seem to be a bit of an advantage with the larger caliber, heavier rounds against glass, but not so much that I would worry about it.

An article in the IWBA Journal regarding deflection testing conducted at the CHP Academy was written: MacPherson D and Fincel E: "Windshield Glass Penetration", Wound Ballistic Review; 2(4):35-39, 1996.

The salient point is, "This deflection angle is not consistent in magnitude or orientation relative to incidence geometry; it seems to be essentially random."

Also of note is that penetration of 5 mm auto windshields reduces projectile velocity by 150-200 fps, while 6 mm windshields drop it down an additional 30%.

Deflection angle is relatively small with .40 S&W 180 gr JHP and .45 ACP 230 gr JHP and due to the random nature cannot be compensated for, thus the authors recommend not worrying about the issue and just shooting normally.

BBMW
08-30-11, 12:00
Would this issue be a factor in choosing the .40 over 9mm?

When I posed this question before, I posed it as G19 vs G23, taking the gun to be equivalent. You preferred the G19 to G23 for reasons other than ammo performance, which basically turned that question on it's head.

So pulling out the issues relating of the gun in question, assuming equal reliability and ergonomics, givng 9mm a one round magazine capacity advantage, assuming the "normal" difference in recoil between the two rounds, and assumng you had the best available ammo for each, would this issue influence your decision whether to carry a gun in 9mm or .40 S&W?



Deflection angle is relatively small with .40 S&W 180 gr JHP and .45 ACP 230 gr JHP and due to the random nature cannot be compensated for, thus the authors recommend not worrying about the issue and just shooting normally.

DocGKR
08-30-11, 12:18
Great thread on this very issue: http://lightfighter.net/eve/forums/a/tpc/f/1931084651/m/34120595763/p/1.

I wrote the following:


After doing wound ballistic research and post-shooting incident analysis since 1989, I've come to the following conclusions:

For CCW and most urban LE duty, there are a lot of advantages in carrying a 9mm--easy to shoot one handed, relatively inexpensive to practice with, lots of bullets. Downside is less robust intermediate barrier capability.

While I am not a big fan of the .357 Sig, if I was issued one and had lots of free ammunition available, I would have no issues about carrying one on a daily basis, however I don't like the blast, weapon wear issues, or cost of ammo. And yes, it is a solution to a non-existent problem...

If I was in a place that issued free .40, was doing a lot of work around vehicles, or had to worry about potentially stopping larger aggressive animals and couldn't generally carry a large bore revolver, I'd be strongly tempted to carry a .40--lots of 180 gr JHP's that do well against intermediate barriers is a good thing. Generally .40's can be harder to learn to shoot well than 9mm or even .45 ACP for many folks. In addition, there are fewer well designed, reliable, durable, accurate .40 pistols on the market.

.45 GAP...

The nice aspects of .45 ACP are that it makes large holes, can be very accurate, offers good penetration of some common intermediate barriers, and is what the 1911 is optimally chambered for. Unfortunately, magazine capacity is less than ideal, .45 ACP is more expensive to practice with, and in general is harder to shoot well compared with 9mm. A .45 ACP makes the most sense in states with idiotic 10 rd magazine restrictions, in places that give you lots of free .45 ACP ammo, or in situations where modern expanding ammunition is restricted due to asinine, illogical regulations.

There was once a very experienced individual who posted here at LF, a veritable tactical rock star, who had the distinction of having carried a 9mm, .40, and .45 ACP into combat during various phases of his career. He was a huge fan of the inherent shootability of John Browing's .45 ACP creation, but acknowledged that the plastic commie G19 was easier to carry and quite reliable. Eventually he began to use the .40 and found it worked very well--lots of bullets that hit hard. He wrote:


"Some people want to make up for their training short falls with a gun that recoils less. OK, but at least call a spade a ****ing spade. Ask yourself which bullet you would rather get shot with. You can show up with ANY 9mm platform you want, and I will bring .40 and if you are not master class bad ass, I will burn you down on a shot timer with full power duty ammo. Recoil management is a nice skill to learn. Other wise I would have just taken up eye socket shooting with a .22 magnum. .40 costs an ass load, but if the ammo fairy allows you to train, then .40 should not hold you back on your split times or shot placement...Ballistic tests on 9mm vs .40? Sorry I just can't buy it. That .40 is smoking hot."

I am quite comfortable with both 9 mm and .45 ACP--the full-size M&P45 w/ambi-safety I am currently using has been completely reliable since it replaced the 1911 I carried from 1986 through 2010, as is the G19 I CCW. However, for uniformed LE Patrol duty use, especially around vehicles, I prefer the .40 cartridge--15+1 offers a lot of bullets; 180 gr has enough mass for intermediate barrier penetration without as much deflection as 9mm and to ensure adequate penetration in tissue AFTER first defeating barriers. The M&P40 is the softest shooting, most controllable, and completely reliable .40 S&W pistol I have yet used; in addition, it is available with the manual safety that I prefer on a LE duty pistol. For those reasons, the M&P40 w/ambi-safety would be my pistol of choice for uniformed LE Patrol duty.