zrexpilot

copied and pasted.
try and understand sport.

The other popular contemporary misconception results from the assumption that the kinetic energy of the bullet is "transferred" to the target, thereby somehow killing it through "hydrostatic shock".
I don't know where this term originated, but it is pseudoscience babble. In the first place, these are dynamic - not static - events. Moreover, "hydrostatic shock" is an oxymoron. Shock, in the technical sense, indicates a mechanical wave travelling in excess of the inherent sound speed of the material; it can't be static. This may be a flow related wave like a bow shock on the nose of a bullet in air or it may be a supersonic acoustic wave travelling through a solid after impact. In terms of bullets striking tissue, shock is never encountered. The sound speed of water (which is very close to that of soft tissue) is about 4900 fps. Even varmint bullets do not have an impact velocity this high, let alone a penetration velocity exceeding 4900 fps. Unless the bullet can penetrate faster than the inherent sound speed of the medium through which it is passing, you will not observe a shock wave. Instead, the bullet impact produces an acoustic wave which moves ahead of the penetration. This causes no damage.
Some people use "shock" in the colloquial sense to describe a violent impact, but it is confusing, especially in connection with the term "hydrostatic" and lends undeserved quasi-scientific merit to the slang. It also tends to get confused with the medical expression attending trauma. We are not describing any medical shock. The word shock should never appear in a gun journal.





The rate of energy transfer to the target is vastly more important than the quantity of energy transferred. This is the technical definition of power. Anyone sunbathing on a clear summer day at the beach will receive an irradiance equivalent to over 4600 ft-lbs every minute! Eventually, this bombardment by extremely high velocity particles will result in sunburn, but the body can withstand the energy it receives because it is spread over a large area and arrives at a relatively slow rate (compared with bullets). The power and intensity (power per unit area) is much less than ballistic events.




Bullets which "overpenetrate" do not stop opponents as readily as those that remain in the body. Therefore, if the energy isn't "wasted" on exit, the bullet is more effective. Right?

Not exactly. A bullet of a given construction and impact velocity will create a cavity of predictable dimensions over its path, whether it stops or penetrates completely. Therefore, if the hole created can penetrate all the way through, it causes more damage than if it stops at some point. The critical issue here is what sort of hole are we making, not whether it goes all the way through. "Overpenetration" is a misnomer. The ineffective stopping attributed to overpenetration is actually caused by "undercavitation".