Hydrostatic shock revisited

[Hank15]

Read it and discuss!

http://arxiv.org/ftp/arxiv/papers/0803/0803.3051.pdf

There isn't a lot of new information, but support for hydrostatic shock was provided.

I'll start the discussion:
What implications does this have for people who use "pocket calibers" such as .380s?

[elSquid]

Probably best to do a google search for:

Michael Courtney hydrostatic shock

...before spending too many brain cells on this paper.

-- Michael

[BigRich]

One of the guns I carry is a Kahr P380. I have chosen to load it with Buffalo Bore 100 gr. hard cast flat nosed rounds. In this caliber and platform I am looking primarily for penetration and whatever damage the meplat will produce on it's way through. The 380 caliber has so little energy that I don't think it can spare what expansion costs and still have adequate penetration. Buffalo Bore says that particular round will do 1050fps from a Kahr P380. That compares well with a 38 snubby, but with 7 rounds on board and a very low profile. I sure wish I had a permit for a long gun too.

[Ronin2]

The article and the concept reinforce the value of the "hammer" double tap and with small caliber rounds (sub 9mm), the need to develop the skill set to perform hammers.

[Bad Caselaw]

Hydrostatic shock, like Anthropogenic Global Warming, is a Hoax.






Caselaw

[Knomad]

Let's assume for a moment that they're correct. Note the recommended minimum threshold of 500 ft/lbs of energy.

Looking at the Speer Gold Dot chart, 357 magnum makes this easily. 357 Sig just barely makes it. 45acp +p barely makes it. That's at the muzzle, all of them drop well under by 50 yards. None of the 40 cal or 9mm loads make it.

As much as I'd like to believe it, I remain skeptical at handgun velocities.

[rm1911]

Self defense is like real estate.

Location location location.

Ideally something like a 30-06 will produce enough shock to incapacitate. But since a garand doesn't conceal all that well, quantity prevails. Hopefully one of them hits something vital.

I got some advice from a cop friend many years ago when he said dump the mag in the first guy. Then reload.

"Save ammo, lose your life"

[Deimos887]

9mm+p+ will just barely break 500ft/lbs, 40+p will hit close to 600, as will 45+p, .357sig will break just about 620 w/the hottest load data ive seen... of course I reload, havent looked @ factory produced load specs in a minute.... no opinion on Hydro static Shock, somewhat knowledgeable on the theory, but not enough to stake a claim.

[digdug74]

I've always thought, and continue to think, that right behind hitting vital organs, the amount of kinetic energy dumped into a target from a projectile is probably the second most important thing in terms of stopping power. It's very hard to watch those slow motion ballistic gel tests showing pressure waves radiating out from the wound channel and conclude that it's meaningless. I think you have to imagine that shock wave causing some kind of damage to the thing that just got shot, either physical, psychological, or some combination of both. If it were purely a matter of hitting vital organs, then we'd probably all be running around with .22lr calibers for self defense and clearly we are not.

[Deimos887]

^ honestly i agree

[ZombieTactics]

This makes the rounds every so often. It's pseudo-scientific nonsense.

Keep in mind that this has not been published in a single, peer-reviewed journal of science.

There's a reason for that.

[Hank15]

I've always thought, and continue to think, that right behind hitting vital organs, the amount of kinetic energy dumped into a target from a projectile is probably the second most important thing in terms of stopping power. It's very hard to watch those slow motion ballistic gel tests showing pressure waves radiating out from the wound channel and conclude that it's meaningless. I think you have to imagine that shock wave causing some kind of damage to the thing that just got shot, either physical, psychological, or some combination of both. If it were purely a matter of hitting vital organs, then we'd probably all be running around with .22lr calibers for self defense and clearly we are not.

That's an interesting observation. When I watch those ballistic gel tests, I always think about the mechanisms for the cavity/wound channel that's many times the size of the bullet. Are they caused simply by the expansion of a bullet displacing the gel? (serious question, someone educate me)

[ZombieTactics]

I've always thought, and continue to think, that right behind hitting vital organs, the amount of kinetic energy dumped into a target from a projectile is probably the second most important thing in terms of stopping power. It's very hard to watch those slow motion ballistic gel tests showing pressure waves radiating out from the wound channel and conclude that it's meaningless. ...

Well it's not "meaningless" but not nearly as meaningful as people would like to make it out.

You first have to disabuse yourself of the notion that kinetic energy is somehow "dumped" into a body. It's not. A handgun bullet can do only two things with kinetic energy ... use it to penetrate, or (as a side-effect of friction) to expand. Energy is "used" to do one of those two things. It is never "dumped", and there is no physical mechanism by which energy even could be "dumped". At the point is has stopped penetrating and/or expanding, it has simply run out of energy.

The "pressure waves" you see in ballistic gel are a side-effect of minor tissue displacement caused by penetration. They don't have enough force to cause any meaningful damage, in the case of handgun rounds.

If you compare the kinetic energy of a typical handgun round to that of the typical punch-with-a-fist, the bullet has more energy. This is a little deceptive, as the bullet uses almost all of it's potential energy in the act of penetrating and expanding. There isn't anything left to "punch" or do blunt-force trauma to surrounding tissue.

A punch to the gut won't penetrate (thank God!), but will create more blunt force trauma than a handgun bullet. Handgun bullets don't physically stop people through blunt-force trauma, they stop people because they put holes in places where there aren't supposed to be holes.

You create more "pressure wave" activity on your internal organs from jumping up and down on a hard surface than from the peripheral effects of handgun bullet wounds.

Think what a gel block would look like if you dropped it from a height of even 2 feet ... it would wiggle all over the place, and maybe even split open in some cases. Your internal organs are designed to deal effectively with that kind of force, or you'd have to be hospitalized every time you hopped down a flight-of-stairs.

In the case of typical rifle rounds (5.56mm, .308, etc.) the story is different. The penetration is so fast and violent, that it creates rapid displacement with enough force to tear stuff up.

If you zing a pistol round right past the heart, not actually hitting or penetrating it ... there isn't going to be any damage or stopping effect. More trauma would be created from a punch right below the ribs on that side of the chest. A rifle round passing by the same structures would likely tear the heart open or rupture connective tissue surrounding it.