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ShootistPRS · June 19, 2017, 08:58 AM

"hydrostatic" shock is a name given to an event caused by the supersonic movement of fluids by a fast moving projectile. You said you wanted to learn about it well this is the truth:
"hydrostatic" shock is neither a static event nor is it a shock. The bodies of animals is mostly salt water. There are fibers and organs that are flexible and suspended in and filled with fluids. When a bullet of sufficient diameter enters a body at supersonic speeds there are a few things that happen very quickly. The leading edge shock wave pushes stuff away from the path of the bullet. Experts call this the temporary wound channel but there is little wounding taking place. This is a dynamic and elastic motion and rarely causes more than a bruise in the local area. At the same time the bullet itself ruptures tissues as it goes through them. This causes bleeding and deep tissue damage. This is what kills the animal. While that is happening the back of the bullet drags a cavitation wave behind it that lowers the pressure momentarily causing "bubbles" similar to boiling but without the heat. This tends to cause the tissues to pull back into the lower pressure behind the bullet collapsing the temporary wound channel and slightly increasing the bruising.
Normally the only killing mechanism is the actual hole and damage that the bullet makes as it cuts through the tissues. There are times - however rare they are that the compression wave hits the heart at the instant it is compressing and causes very high blood pressure throughout the animals vascular system that sometimes causes hemorrhage in the brain. The animal collapses so fast that it appears to be knocked over by the impact.
We can see the hydrostatic shock is neither static (without movement or change) nor a reliable killer. It is reliant on two things;
1. speed over the speed of sound
2. the physical size of the projectile
If you can imagine a sewing needle at 20,000 feet per second going through a deer you can "see" that there would be very little tissue movement and very little damage to organs. The needle would go right through and the animal might or might not be aware that it was shot. The small wound would heal in a day or so and the animal would be unaffected.
a 30 caliber bullet hitting the animal at 2300 fps will produce a large frontal compression and cut a hole through tissues big enough to provide for a loss of blood that will kill the animal.
A 12 pound bowling ball traveling at 300 fps will break bones and cause huge ruptures in tissues that will kill the animal quickly even though it is not travelling anywhere near the speed of sound. The internal damage will be caused by broken bones cutting and tearing the inside of the animal.
The truth behind "hydrostatic shock" is that it is a made up name for a reaction that has little value in the quick and clean killing of a game animal.
I hope this gives you the information that you are looking for.

June 19, 2017, 08:58 AM	#6
ShootistPRS Senior Member Join Date: January 3, 2017 Posts: 1,583	"hydrostatic" shock is a name given to an event caused by the supersonic movement of fluids by a fast moving projectile. You said you wanted to learn about it well this is the truth: "hydrostatic" shock is neither a static event nor is it a shock. The bodies of animals is mostly salt water. There are fibers and organs that are flexible and suspended in and filled with fluids. When a bullet of sufficient diameter enters a body at supersonic speeds there are a few things that happen very quickly. The leading edge shock wave pushes stuff away from the path of the bullet. Experts call this the temporary wound channel but there is little wounding taking place. This is a dynamic and elastic motion and rarely causes more than a bruise in the local area. At the same time the bullet itself ruptures tissues as it goes through them. This causes bleeding and deep tissue damage. This is what kills the animal. While that is happening the back of the bullet drags a cavitation wave behind it that lowers the pressure momentarily causing "bubbles" similar to boiling but without the heat. This tends to cause the tissues to pull back into the lower pressure behind the bullet collapsing the temporary wound channel and slightly increasing the bruising. Normally the only killing mechanism is the actual hole and damage that the bullet makes as it cuts through the tissues. There are times - however rare they are that the compression wave hits the heart at the instant it is compressing and causes very high blood pressure throughout the animals vascular system that sometimes causes hemorrhage in the brain. The animal collapses so fast that it appears to be knocked over by the impact. We can see the hydrostatic shock is neither static (without movement or change) nor a reliable killer. It is reliant on two things; 1. speed over the speed of sound 2. the physical size of the projectile If you can imagine a sewing needle at 20,000 feet per second going through a deer you can "see" that there would be very little tissue movement and very little damage to organs. The needle would go right through and the animal might or might not be aware that it was shot. The small wound would heal in a day or so and the animal would be unaffected. a 30 caliber bullet hitting the animal at 2300 fps will produce a large frontal compression and cut a hole through tissues big enough to provide for a loss of blood that will kill the animal. A 12 pound bowling ball traveling at 300 fps will break bones and cause huge ruptures in tissues that will kill the animal quickly even though it is not travelling anywhere near the speed of sound. The internal damage will be caused by broken bones cutting and tearing the inside of the animal. The truth behind "hydrostatic shock" is that it is a made up name for a reaction that has little value in the quick and clean killing of a game animal. I hope this gives you the information that you are looking for.