By now, most of us have heard the gel-based theory that has been oversimplified to state that all service handgun cartridges have the same terminal effectiveness. The theory rules out any effect from hydrostatic shock because it is not consistently witnessed where impact velocities are below 2200 fps in common handgun calibers. According to Federal's Johann Boden, because the organism's (human's) tissue has an elasticity that is able to absorb the energy imparted through "temporary wound cavities", there is no meaningful permanent effect. Or is there? Beginning at 5:06, Johann begins to explain this elasticity thing. He describes the "temporary wound cavity" appearing too fast for the human eye to see in human tissue, which he explains is made largely of water. I can't help but think that Boden, as well as possibly Boone, learned about humans from gel. Anyone who has shot a pumpkin, which is also largely made of water, knows that they don't explode the way a watermelon does, which is also largely made of water. The difference is that the pumpkin is also full of compressible gases like air. Humans and most mammals are similarly full of compressible gases. It's not just the elasticity of Jello-brand tissue in the organism that stretches to absorb the hydraulic force of the bullet's impact displacing the matter in its path. A lot of it is just gas. Anybody that's ever field-dressed a deer knows that it's more like a pumpkin inside than a watermelon. There is a lot of hollow space, and we wouldn't describe it as "mostly water" unless we ran it through a woodchipper into a bucket first. At 5:46, Johann tells us what's left after the recovery from the rapid stretching of Jello is the "permanent wound cavity, namely the crushing path" the bullet took. He then goes on to describe how at velocities above 2200 fps, the elastic threshold of the tissue is exceeded and the tissue tears at a much greater diameter than the expanded bullet's path. Johann is simplifying some things here for the sake of brevity. I'm sure he understands this better than only the necessary explanation he gave impromptu. If I were to explain in a little more detail, I would propose the velocity thresholds involved in terminal ballistics are caliber-sensitive. The research I've studied suggests a threshold of around 2200 fps for 35 to 40 caliber projectiles. With a larger projectile like a 45, the threshold may be as low as 1800 fps. With calibers 30 and under, the threshold may be as high as 2600 fps. Since this is all only relevant to rifle ballistics, its not hard to see why Johann glossed it over. But there are a couple of other issues that are relevant to handguns. One I think is missing that we need to understand is that either velocity and larger caliber do contribute to greater wounding even at velocities below the thresholds mentioned. The other thing is that so does the width of a flat meplat. Anyone that has shot game mammals will readily recognize that bullets that impact below Boone's velocity thresholds most certainly can produce wound cavities much larger diameter than the caliber. Johann acknowledges this but glosses it over. At 7:15, Johann attempts to explain what happens to the energy of more powerful handgun rounds so that one is not meaningfully more effective than another. Using the 44 Magnum as an example, compared to a .40 S&W, Johann explains the additional energy of the Magnum is simply absorbed within the elasticity threshold of human tissue. This is simply balderdash. Of course, most often, the additional momentum of the heavy magnum's bullet is simply carried through the body and imparted to a backstop somewhere else. But the question was asked about higher energy rounds that do not penetrate more. The 44 Magnum is probably a poor example of this, but we can certainly see examples of much higher energy ammo not penetrating deeper than lower energy ammo even though both rounds expanded about equally. Look at these two rounds for a good example: Be sure to choose the drop-down to compare the data for Ruger GP100, barrel length 4" https://www.luckygunner.com/357-mag...h-short-barrel-buffalo-bore-20-rounds#geltest https://www.luckygunner.com/357-mag-125-grain-hp-barnes-tac-xpd-20-rounds#geltest If you're looking at these test results, and you've selected the 4-inch test barrel data, you'll see that with the Barnes 125 grain bullet, a 5-shot median penetration and expansion of 16.3" and 0.69" were achieved at a median velocity of 1416 fps or 556 foot-pounds of energy. Also, with the exact same Barnes 125 grain bullet (save for the color), a 5-shot median penetration and expansion of 16.2" and 0.72" were achieved with a median velocity of 1287 fps or 460 foot-pounds. Where did the extra 96 foot-pounds of energy go? Well, in this case, it jiggled the Jello. It's easy to see where Johann gets his theory. In this case, 96 foot-pounds might not make a noticeable difference on a game carcass either. But Johann is comparing a 1044 foot-pound 44 Magnum to a 361 foot-pound 40 S&W (using his specs), and he claims at 7:36 that it, "does not seem to translate out into a corresponding amount of damage in a human organism." He says he believes that is because we just stretch around it, as it's within that elasticity threshold. But then at 7:50 he admits, "Does it make a bigger, more significant wound than say a 40 cal or 9 millimeter, yes it does, but really not enough to matter, to change the outcome of a critical event." Now anyone that has seen the wound of a .40 S&W on a deer and the wound from a .44 Magnum on a deer might need this double-talk to be explained a little better if they are to believe it. First of all, it should be acknowledged that finding a 240 grain .44 Magnum bullet that at 1400 fps does not penetrate better than a .40 S&W would be impractical. Not all of the .44 Magnum's additional 683 foot-pounds of energy will be transferred into wounding as it will almost certainly over-penetrate, but it is almost certain that the net transfer of energy will be greater than that of the .40, unless the bullet was intentionally designed to avoid this. The bullets in any of the more powerful cartridges are going to have to be constructed so as to transfer as much energy as is practical while maintaining sufficient momentum to achieve a depth of penetration according to their target if they are to wound most effectively. What I think is missing in this apparently prevailing theory of the absence of hydrostatic shock in handgun terminal effects, is a distinction between the capability of a projectile to induce coma through hydrostatic shock at handgun velocities, and the capability of a projectile to produce wounding through hydraulic pressure. I believe the Boone velocity thresholds do not determine a bullet's ability to produce a much larger than caliber diameter permanent wound channel with hydraulic pressure. These thresholds have been misunderstood. Where these thresholds are relevant is with regard to the ability of a projectile's impact to cause a hydrostatic shock wave that induces coma. Coma is probably achieved by a spike in blood pressure resulting from the shock wave (rather than the bullet) hitting the central nervous system. The result of this mechanism is very similar to a knock-out punch. It is the immediate, but temporary incapacitation of the person or animal through coma or loss of consciousness. The permanence of this incapacitative event is dependent on the severity of wounding and blood loss that must result in total disablement or death before the animal regains consciousness. The hydrostatic shock is not the chief mechanism of the wounding, but the bullet crushing tissue in its path and the hydraulic pressure of the fluid it displaces are. In the absence of the practicality of achieving immediate coma without direct hits to the CNS, does it make sense to also dismiss the ability of a bullet to produce a larger than expanded-caliber wound? Johann says this greater wounding does not matter enough to change the outcome of a critical event. Do you agree? Now there is a separate issue relating to the justification for replacing .40 S&W with 9mm. About this, Buford Boone himself has written, "Without getting into the weeds, a full power .40 is a great cartridge. Unfortunately, most shooters and many pistols can't actually handle a full power .40. Put a problematic pistol in the hands of a problematic shooter and you've got guaranteed catastrophe." This is clearly a pistol and shooter problem, not a cartridge problem. The weight of the pistol and the skill of the shooter can be increased to the points where this is made irrelevant or overcome. Boone goes on to say, "So far as the more powerful cartridges go, my personal opinion is that nobody should even be allowed to carry them unless they are able to consistently max out the qualification course." Again, the weight of the pistol can be increased to the point where there is no perceptible difference to the shooter, and if their skill is equal with the lighter gun, then there is no issue. But what we have are people selecting cartridges based on how far the gun they can shoot them in pulls their pants down, rather than on what effect the bullets are having on the target. What's worse, is we have ballistic analysts and technical consultants that are justifying less effective cartridges by disingenuously claiming, "they're all the same."