Pressure Waves

A friend of mine has been working on a project for his doctorate, and let's just say it has to do with pressure-wave theories. This simply cuts through all of the jawbreaking jargon and makes it gun-specific.

For decades, there has been an ongoing debate about what used to be, and for that matter still IS referred to as hydrostatic shock. Way back when, hunters and military men would opine that certain bullets seemed to be doing a lot more damage than could be accounted for by mere caliber alone. Those that poo-poo'd the idea drew voluminous diagrams of bullet configurations and whatever else they could come up with to dismiss anything to do with a wound-inducing pressure wave generated by the combination of just the right bullet going just the right speed.

Now, I detest even the very mention of hydrostatic shock. Seemed that every otherwise braindead "genius" loved the sound of the word and would repeat it at whatever provocation to describe ANY anomoly associated with wound ballistics.

"Gotta be yer hydra-statics workin' there, ahuh." And of course Federal nearly ruined shooting for me with the advent of their Hydra-Shok rounds that just tripped off of the tongue of many, many, of the walking dead who share my atttraction to firearms.

Nearly. The bullet itself sucks but I don't want to get into it now, so let us move on for the time being.

So merrily we road along, accepting aberration upon aberration, for to mention anything to do with pressure waves drew instant villification, and did I mention that I hated hydrostatic shock as spoken by one toothless Ted after another?

Then came the end of the 20th Century. New bullets were changing old perceptions, and people - with actual educations, mind you - were looking at the problem with...lo and behold...a scientific bent.

Hating hydrostatic shock for all the wrong reasons, I nevertheless saw too many instances of blowed-up-real-good to irrevocably dismiss the idea. And the bottom line SEEMS to be that the pecularities created by light and VERY fast bullets is directly connected to pressure wave theory, and pressure waves CAN be a respectable adjunct to diameter and construction with regards to inflicting wounds.

So we're shooting at 35 pound calibrated gelatin blocks. Sitting on a "cold-plate", and unsecured. By that I mean the block just sits there and isn't tied down.

And a funny thing happened on the way to the firing. Each and every round that exceeded 130 grains in weight and 1400 feet per second very nearly knocked the gel-blocks off of the plate. Modern bullets all seem to penetrate 12 to 14 inches, blah-blah, but the sound of the impact and WATCHING the gelatin quiver was something else entirely.

And bullets weighing over 180 grains and traveling at speeds around 1000 fps did the same thing.

SPLAT. Followed by a sideways twist of the 35 lb. block. Go much under 1400 fps for the lightweights and they simply hit and dug in. Take the big boys and lower the giddy-up to under 950 fps, and samey-same.

Sometimes it boils down to who are you going to believe? The math, or your own eyes? Kinetic energy is the potential for doing work. Ballistic gelatin can determine what a particular round will do when impacting ballistic gelatin.

But the SPLAT. The SPLAT.