Cor-Bon DPX

[Burt Blade]

One problem with the science of terminal ballistics: the darn perps won't follow the studies! Some of these felonious morons just cannot read the box that promises Dead right There!

So what to do? I generally look at JHPs as “bonus” rounds. If it actually expands, it is a bonus. If it will work as a solid, then I can accept it. A 230 grain .45 FMJ can reliably be counted upon to produce an approximately .45 caliber hole. A 230 grain .45 JHP should not do any less. Does it also feed 100% in my 1911? OK, we have a winner. 230 grain HydraShock works for me.

You cannot with certainty count on a JHP round to prevent over-penetration, or to “smithereen” your attackers innards. You may get a bonus of enough effect to make up for less-than-ideal placement. But even fully expanded and spot-on-target, it may still exit and continue on.

Actual controlled-study field-tests of defensive ammunition in realistic conditions are rather strongly frowned upon by most of civilized society and the law, so we have to make do with soup bones and jello, and comparisons to various four-legged critters.

And it certainly keeps folks busy on forums like this.

 

[orionengnr]

Pretty much every pic of a fired DPX looks exactly like the one above.

Doesn't matter if it's been fired through water, ballistic jell-o, denim, plywood, what-have-you...

The genius of the DPX design is that it provides predictable, consistent expansion no matter what.

 

[Loosedhorse]

When the FBI was deciding to adopt 10% ballistic gelatin as its standardized test medium it compared terminal performance data from over 200 shooting incidents to terminal performance data obtained from shooting bullets into ordnance gelatin.

I'm not sure what you mean by this. Perhaps, that they have 200 incidents where a given round penetrated 11.5 inches in gel, and also stopped 11.5 inches into the person shot? With each bullet beginning to tumble at 5.3 inches? Or just "generally consistent"?

Bone simulants have also been found to correlate well with the morphological characteristics of real gunshot wounds. For example:

In our experiments, gunshot lesions produced in the artificial skin had the morphological characteristics of real firearms wounds. Consequently, it was possible to reconstruct the morphology of distant gunshots, especially the characteristic signs for the entrance wound: the ‘‘abrasion ring’’ and the ‘‘ring of dirt’’. It was also possible to reconstruct the semilunal abrasion of the gunshot wound specifically caused by tangentially striking projectiles, which abrasion also indicates the direction from which the gunshot came.

Furthermore, it was possible to study the development of a glancing gunshot wound. It is known that the direction from which a projectile is fired can be determined by a careful examination of the gunshot wound. Specifically, the
observation was made that the ‘‘skin tags’’ [12], located along the lateral margins of the glancing wound, point toward the weapon, or, expressed in another way, point in the direction opposite the flight path of the projectile.

With the model, we could reproduce this morphology, and with the high-speed photography it was also possible to document the ricochet away from the skull. The physics of the ricochet is responsible for this special wound morphology
[20].

 

[Shawn Dodson]

A 230 grain .45 FMJ can reliably be counted upon to produce an approximately .45 caliber hole.

The "hole" produced by an undeformed, unyawing round nose FMJ bullet averages about 65% of its caliber. The hole is larger at the beginning of the wound track and tapers down in diameter as the bullet penetrates.

 

[Shawn Dodson]

I'm not sure what you mean by this. Perhaps, that they have 200 incidents where a given round penetrated 11.5 inches in gel, and also stopped 11.5 inches into the person shot? With each bullet beginning to tumble at 5.3 inches? Or just "generally consistent"?

The "damage" produced in gelatin, as well as the bullet's terminal performance characteristics, have been verified and validated directly to the "damage" and terminal performance characteristics observed in live human soft tissues from actual shooting events.

Bone simulants have also been found to correlate well with the morphological characteristics of real gunshot wounds.

Unfortunately there are no data to show that BrassFetcher's bone simulant test protocol has been verified and validated against results from actual shootings to prove that the terminal performance exhibited in its test results depict a reasonable indication of terminal performance observed in actual shootings under identical conditions.

 

[Burt Blade]

Keyword "approximately". Wet somewhat squishy stuff tends to squish. It won't read the darn "DRT" box, either.

I expect to get a .45 pattern/size/whatever wound channel based on bullet size, speed, and mass. The solid slug doesnt typically shrink much. The JHP might or might not grow. If it does, bonus.

 

[Loosedhorse]

Unfortunately there are no data

Again, not sure what you mean. You seem to take as "data" that gel has been "verified" as expert opinion that "damage" in gel resembles "damage" in humans.

The paper I cited also said that the "damage" seen in their simulated skin/bone/flesh model correlated with the "damage" seem in actual shootings--right down to the direction of skin tags, characteristic surface markings, and bone cracks and punctures. Even damage from glancing shots was well simulated.

 

[Shawn Dodson]

Again, not sure what you mean. You seem to take as "data" that gel has been "verified" as expert opinion that "damage" in gel resembles "damage" in humans.

It's been more than 2 decades since FBI adopted 10% ordnance gelatin as a realistic soft tissue simulant. Since then the 10% ordnance gelatin test model has been independently verified and validated by many other reputable researchers and organizations (engineering, scientific, medical, law enforcement, military) - who've directly compared the disruption produced in ordnance gelatin to the disruption produced in the human body by the same projectile under identical circumstance.

The paper I cited also said that the "damage" seen in their simulated skin/bone/flesh model correlated with the "damage" seem in actual shootings--right down to the direction of skin tags, characteristic surface markings, and bone cracks and punctures. Even damage from glancing shots was well simulated.

The study you cited does not validate the the Brassfetcher test methodology. It validates the specific circumstances of a bullet glancing off bone and the damage produced in skin. BrassFetcher's test is entirely different.

BrassFetcher's test has the bullet perforating 1) rubber, then 2) bone simulant, and then penetrating 3) gelatin. To be verified and validated as an accurate test model it MUST be compared to actual shootings UNDER IDENTICAL CIRCUMSTANCES THAT THE TEST IS PURPORTED TO REPRESENT in which bullets perforate the sternum and penetrate the thorax.

 

[Loosedhorse]

who've directly compared the disruption produced in ordnance gelatin to the disruption produced in the human body by the same projectile under identical circumstance.

"Directly compared"--how? Slice by slice microscopic section? Because of gel's transpacency, measuring tacks' length and width is relatively easy; not so easy with a body, as a thick microsopic section is about 50 microns. Through a (conservatively estimated) 10-inch thick thorax, that's a lot of slices!

Other ways of examining a human wound track (incision/eversion, latex casting etc.) leave their distinctive artifacts.

under identical circumstance

Again, what does this mean? Both the human and gel were shot through a flannel shirt at 4 ft with the same gun at 70 degrees ambient temp, 20% humidity, 1.0 atm?

That brassfetcher's methodology has not been compared to "identical" human shootings is not disputed. I'm just trying to evaluate your claim that ordnance gel shootings (especially the current ones, through auto glass, clothes, etc.) have in fact been "validated" to the extent that you feel are necessary for brassfetcher's tests.

Perhaps it would just be easier to point me to one or two of the studies that list the compared metrics (as opposed to any studies that simply state the conclusion that the metrics are "similar") for gel shootings and the specific (cadaveric? war-time? LE?) human shootings that were used for comparison...

Wiki, for example, lists no such papers. One of the papers wiki does list makes no mention at all of human comparisons. It even mentions that the validity of gel in regards to simulating swine muscle is not clearly shown by studies:

Although the paper did not include specific comparisons between gelatin and animal tissue, the [Letterman Army Institute of Research] team and many other researchers afterward cited this published paper as the foundation for using Fackler’s gelatin model as an approximate or equivalent substitute for animal tissue

 

[Shawn Dodson]

"Directly compared"--how? Slice by slice microscopic section? Because of gel's transpacency, measuring tacks' length and width is relatively easy; not so easy with a body, as a thick microsopic section is about 50 microns. Through a (conservatively estimated) 10-inch thick thorax, that's a lot of slices!

Visual, physical and radiographic examination of the wound.

Again, what does this [under identical circumstances] mean?

I refer you to Fackler's 7 page paper in post #25. (I'm in Seattle right now and I won't be home for another couple of weeks. If you'd like, when I get back home I can scan it and send to you.)

That brassfetcher's methodology has not been compared to "identical" human shootings is not disputed. I'm just trying to evaluate your claim that ordnance gel shootings (especially the current ones, through auto glass, clothes, etc.) have in fact been "validated" to the extent that you feel are necessary for brassfetcher's tests.

Perhaps it would just be easier to point me to one or two of the studies that list the compared metrics (as opposed to any studies that simply state the conclusion that the metrics are "similar") for gel shootings and the specific (cadaveric? war-time? LE?) human shootings that were used for comparison...

You can start with many of the the references in the paper you linked. (I visited Stanford University 20 years ago and copied many of them for my library.)

 

[Loosedhorse]

If you'd like, when I get back home I can scan it and send to you.

That is a very generous offer. I thank you. It would seem best in the interim for me to hold off with any more questions, as that paper may have all the answers I'd like.

Wishing you a safe and successful trip.