Home Forums Hunting & Shooting Deer Hunting Hydrostatic shock: Mystery or Myth? My theory

I just responded to another post titled "slow or fast moving bullet" debate.

I think anyone with an IQ over 80 would agree that what kills a deer has nothing to do with "how much time a bullet spends inside a deer" but rather....what that bullet does WHILE INSIDE the deer.

Then...someone responded with the idea that a fast moving bullet creates a "hydrostatic shock" to the CNS. Terrific. The theory of hydrostatic shock is not a new one. Roy Weatherby has sold thousands if not hundreds of thousands of rifles on this theory. It is (in a nutshell) that the tremendous displacement of water in the tissue creates a wave that overloads the CNS and shuts the animal down.

I have had one experience where I shot a smallish whitetail deer with a very fast moving and very frangible .30 caliber bullet. I hit him right in the heart/lung area with the 150 grn bullet arriving at just over 3,000 fps. After the shot...the deer stood there for a second looking around...and then nearly went back to eating before it lifted up his head and started to run. He ran well over 100 yards before he fell over dead.

Needless to say...damage to the deer's lungs were massive. If there was any credibility to the "Hydrostatic Shock" theory...then he'd have fallen over as soon as this massive shock wave was set up in his body.

Bunk.

Here is my theory:

Bullet technology has advanced over the last 15 years and has given us some fantastic bullets that can be pushed to ultra velocities and keep together.

But in the 50's, 60's and 70's....the same bullet being used in a 30-40 Krag was being used in the .300 Magnums of the day. The bullet the manufactures loaded the .257 Roberts with were also finding their way into the chamber of a .257 Weatherby. Same for other hot rod numbers of the day.

The very fast driven velocities as in the .257 Weatherby and others could produce some spectacular one-shot kills. Roy Weatherby called this phenomena "Hydrostatic shock". The same thing that would instantly stop deer and antelope in their tracks would frequently fail to penetrate larger, heavier game because the bullets would blow up on a shoulder. Hence the need for premium bullets that would stay together at even the fastest velocity.

A non-premium fast moving bullet is likely to fragment when it hits anything solid and often times will fragment on muscle tissue itself. Bone that is hit will also fragment, flying off in all directions. If any of these fragments hits the spinal column....you could get the same results as a true neck shot. I have yet to see anyone with this theory...so it might also be bunk....but it would seem to make as much sense as anything else to explain these dramatic lightening fast kills on a heart/lung shot deer.

Thoughts?

I think there is something to the theory, but I can't explain it. I do know that I went from a .243/95gr as a kid to a .270/130gr as a teenager to a 300WinMag/150gr in college and the 150 Ballistic Tip at high velocity put many deer on the ground with straight-up lung shots. It was something like a dozen in a row, in their tracks. The ones that did run did not make it more than 10-15yds and I didn't always get exit holes. Couldn't say the same with the 243 and 270 using similar bullets.

Fill a large can (3 lb. coffee can or #10 can) with water and sit it on a post, stump, box or similar flat, level surface. Place a similar can empty on top of the water-filled can. Now, shoot the bottom can dead center from 50 yds. with your favorite deer load.......What happens to the top can?

Couple of thoughts...

1.) 3,000 fps I would not consider a good example to debunk or bunk the hydro-shock theory. Bullet is too slow and LOTS of calibers/cartridges can push a bullet this fast. Roy Weatherby, who you cite, especially with his signature cartridges would not consider this "fast". You cite a .257 Roy, which is probably a great example of this theory, that can push a 85-100 grain waaaayyy fast yet you debunk the hydrostatic shock theory with 3,000 on one deer fps?

2.) One example of one deer proves nothing. Too small a sample size my friend.

I do believe, and I have seen it many, many times in small bores (read .224 bores specifically as it relates to your post in the .223 deer thread below) in which the animal dies so quick they bounce. There is magic, irregardless of bullet diameter, in pills, irregardless of weight, that are pushed very fast.

I'll leave it up to ya'll to determine the how and the whats, all I know is what I've seen in the field...

OK, let's throw this in also. I shot a deer in the neck one time and the shot missed the bone and hit an artery. The deer fell at once and lay there frozen. I knew that it wasn't good but his rear end was toward me and I did not have a good angle for a follow up shot. I tried to watch and shoot again when he got up, but it was too fast and I missed. He ran into the woods for about a hundred yards but died from blood loss. There was enough shock to his spine to paralize him for a little while even though the bullet was far enough away that it did no damage to it. I looked close when butchering him and there was no bruising or blood spots from bullet fragments near his spine. When he fell he was drawn up in a knot like a beef when you shoot him in the brain with a 22 rifle. miles

Not sure how to say what I want to. I think there is a shock wave created. Otherwise a bullet that holds together would simply punch a hole in a deer. If this were the case, the deer would need to die from blood loss. If we were looking for deer to die from blood loss, I do not know that an arrow would not be a more appropriate tool. Do I believe that it is this shock that kills the animal; no. The wound created by the bullet is much larger than the bullet diameter at recovery because, I believe, the shock wave helps �tear� the meat. I also believe that there is a wave created that may do some additional damage, but not enough to kill the deer. If the shock wave alone was enough to kill a deer, bullet placement would not matter.

That being said, I am not opposed to the magic theory and would love a more scientific explanation.

You guys keep it up and Dober is going to get on you for talking ballistic gak this close to deer season.

I wish I could go back in time with an Uzi and prevent the term 'Hydrostatic Shock' from being thrust upon the world. You just can't have a shock wave in an incompressible fluid... water, blood, whiskey (Kool-Aid anyone) are all ineligible.

I'm not denying that you can get damage far from the bullet path. I don't know but what the difference between bullet construction or speed might cross a line in the amplitude or frequency of the wave that is generated and cause instantaneous death from a thigh wound. Who knows?

But we do know that this wave that is generated will not be a shock wave.

Don't take my word for it read for yourself. Google up 'normal shock wave relations' and go to any reputable fluid dynamicist and they will tell you exactly what I have.

I vote we coin a new term for this phenomena: High Amplitude Hydrodynamic Wave... which is exactly what we are talking about here. Aside from that I have no problems with any argument one way or the other.

Will

I will not get sucked into an argument... I will not get sucked into an argument... I will not get sucked into an argument.

PD

I've been in on a few kills over the years, generally speaking many more than average folk IMHO.

A local older fellow shot 4 or 5 deer each year on the lease. He shot only a 220 swift with 50 grain HPs. He shot each deer in the flank. Flank as in between the last rib and the hindquarter, mid ways up. Every last one was an instant bang flop. Never saw an exit. MV was reported over 4000 fps according to their old chrono. They did not load mild rounds.

Was also my first exposure to the gutless cleaning method... thats been over 20 years ago.

There is some theory thats valid about a fast frangible bullet and some type of shock.

Jeff

I think hydrostatic shock has some merit for anchoring-stopping dangerous game or close in self defense..BUT...........
on deer?

Sheesh..Just get the bullet in the heart lungs or CNS and it can even be a .22 caliber one doing 1400 FPS at muzzle and they die pretty fast..unless you can't track more than ten yards..or move the quad a bit closer..:)

Less meat damage with the smaller slow moving calibers too..:)Jim

Oh goody, hydrostatic shock! Now I will get a 300 RUM, shoot 130's as fast as I can, and put a bullet hole through their ears! It might not kill, but hey, all that shock will a least knock them to the ground!
I'm with jim in oregon. What makes them drop from a 260 gr. 45 cal. at 800 fps?

Penatrate vital organs and shut down CNS and you will have a dead deer or what ever your shooting at. Heavy caibler and moderate speed+ good bullet proformace= dead animal.

Ed

if you have not personally tried a 80 gr projectile @3700 fps, then how can you comment with wisdom?

Does it have to be 3,700, or is 3,450 close enough? Ok, how about 55grs. at 3,700? Yes, I have done it, they worked, but I saw no magic since the bullets hit the right place. Have you personally used a wide meplat handgun bullet or deer slug? I think you can get the tissue spray (permanant wound channel) and temporary wound channel (count the elastic nature of offside skin as well) more ways than high speed alone, and there is less clotting around the PW channel. Just throw a boulder into water, then a rock as fast as you can throw it, same crap, two different ways. Please shoot everything with the highest speed/ highest shock loads you can up the keister and report on how they have their azzes shocked to death. The rest of us will use crap from bows to 3,000 ft loads and try to put holes where we're supposed to.
Oh yeah, Roy said you could hit them anywhere too.
Another thing, any of you who have shot PD's have probably seen them literally in half, yet make the "crawl" back to the mound, and they were not shot with a 22RF!
Enough of arguing, good luck hunting everyone, regardless of what you use!

You and Penguin can both be right! Roy never said that high
volocity compressed that which is incompressible; he said that
the very high velocity actually caused the blood to run backward in an animal's veins (because blood won't compress
so it has to run backward from the 'shock'). He's probably only
talking about a quarter-inch or less, who knows, but that's his
version of hydrostatic shock, rightly or wrongly.

Your thoughts, guys?

Could care less about hydrostatic shock. I shoot em in the lungs and they die, then the family eats em.

Yeah, but how far you gotta chase 'em? I'll bet they don't
usually end up DRT when you lung-shoot 'em, right?

Hey, can you use .223 for deer in PA?

I don't know if it's hydrostatic shock or something else, but a fast moving projectile causes a big hole through vital tissue. I have killed or seen killed a bunch of critters with slow moving large diameter projectiles such as shotgun slugs and 50 cal muzzleloaders and the wound cavity is typically larger by a high velocity centerfire of even relatively small diameter such as 24 or 25 cal. Doesn't necessarily always result in drop at teh shot results, but I don't buy the argument that velocity doesn't buy you anything other than trajectory.

Lou

Yes a 223 is legal ( 22 cal centerfire) in PA.

Gotta truly admit ain't never had to "chase" one. Found all of em dead within 40 yrds of so.

RE: Above-mentioned can experiment -- Have done it many times: Shoot the bottom can that is full of water, and the empty top can flies several feet into the air. Why? It was not hit.....What provided the force to propel it into the air?

Magic, I bet!

I've seen more "bang flops" from mid-range 45-70 loads than anything else.