Does kinetic energy actually affect the terminal ballistics (or "stopping power") of a bullet?

Question

I am extremely frustrated with this question because of all the different sides I hear about it. Some say that penetration and caliber are all that really matter because kinetic energy only affects the temporary wound cavity, which can sustain an incredible amount of damage. I have also heard that overpenetration can be a good thing because all the kinetic energy of a bullet in flight does not need to deposit in the body for it to be effective. So does kinetic energy really have little to no impact on the damage of flesh? An additional factor to be considered is whether or not kinetic energy is only irrelevent to the effectiveness of PISTOL rounds due to their generally low velocities. Perhaps the allegations that kinetic energy has nothing to do with stopping power only applies to (lower powered) pistol rounds.

Answer 1

two answers.
get Evan marshals book on stopping power based on actual shootings of humans from police records. its hard to argue with data based on actual shootings. according to that data a 125 gr. 357 has the best % of 1 shot stops, better than the 44 mag or any other hand gun.
personal experience. I have shot many deer over the last 40 years with everything from 243. to 45-70 including45 to 54 cal muzzle loaders &357 to 45 cal pistols & bows & arrows. the high velocitys (2900 FPS & up) kill a lot quicker usually instantly. hand guns are like arrows no mater where you hit them it takes a while to find them. the big bores leave a better blood trail especially with a heart shot, but a 243 or 270 or 7 or 300 mag at around 3000 fps will usually drop them where they stand. the weight of the bullet doesnt seem to be as important as the speed although the shock ruins a lot of meat. with hand guns you cant get enough velocity to make much difference so for game animals bigger seems to be better as they all go all the way through & dump their energy in the woods on the other side.

Answer 2

Stopping power is more than just kinetic energy alone, or velocity alone. It is a combination of energy, velocity, bullet construction, shot placement, and the state of mind of the person or animal shot.

To explain, let me mention a story that Evan Marshal, a noted ballistic, and stopping power researcher, told of two shooting victims. One was a bankrobber. He'd caught 4 full power .44 RemMag slugs in his torso. The bandit WALKED to the ambulance, survived and stood trial ane was convicted. He refused to die. The other was a rookie cop who'd been shot throught the fleshy part of his upper arm with a .25 ACP. It was the kind of wound that required only cleaning, and a bandaid on each side with light duty assignments for a week. The young cop went into shock and died. He'd been shot and he believed that gunshot wounds were invariably fatal.

Don't get me wrong, I am not advocating the use of .22, .25, or .32 handguns as great self-defense cartridges. I am simply indicating that there are times when caliber and power do not influence the outcome.

I wish I had some sort of magic formula to use to tell you what the best cartridge choices would be, but I don't. I can tell you that I, and most experienced gun cranks will tell you is that the .38 SPL is the minimum you should consider for a serious defensive round. Not because of it's tremendous velocity or power, but because it has a long track record as a good manstopper.

Are there better defensive cartridges than the .38 SPL? Sure! The .357 Mag, .41 SPL (not magnum), .44 SPL, .45 LC, .45 ACP are lots better in power and velocity and energy, and the 9 mmP is at least as good as the .38 SPL.

When it comes to hunting, over penetration is good. Especially if shot placement is less than perfect. It makes another hole to let blood out and air in, it makes tracking easier, and it speeds the time it will take for the animal to bleed out. Defensively speaking, over penetration can be bad, mainly because it endangers innocent bystanders. That is one reason FMJ bullets and nearly all .41 Mag and .44 RemMag ammo is terribly over powerful for defensive use.

But like I said, I have no magic formula. All I can tell you is to study the problem from both sides, because neither school holds ALL the truth. Caliber, velocity, bullet weight, bullet construction, and shot placement are all variables to consider. Ignoring any of those factors can lead to error.

BTW, no handgun round has enough velocity to create a lot of hydrostatic shock. That requires 2000 fps or faster.

Doc

Answer 3

It's an old argument that refuses to die. Experience shows that energy overemphasizes the importance of velocity, and momentum is a better measure when you're talking about big bullets in which expansion is not an emphasis, as with a lot of handgun bullets or solids in dangerous game. With bullets that expand properly, and bullet mass constant, perhaps the correct answer is not to multiply by either velocity or the square of velocity but something in between, perhaps velocity to the power of the square root of two.
Certainly permanent wound channel is more important than temporary cavitation, at least on a chest shot (though perhaps not with a brain shot). I suspect some of the dramatic drops we see in the field even have something to do with whether the game's heart is in the vulnerable phase of depolarization when we make a heart shot. There will probably never be an end to this argument, but older hands just want to caution that it's easy to mess up using too-small bullets at high velocity. Taylor wrote his bit to save lives in Africa. Most of us won't be killed by our prey, but we owe it to them to use enough gun.

Answer 4

Easy question to answer if you think it through.

A hypothetical question for you, though....

Would you rather be shot in the chest with a .357mag and have it stopped by a ballistic vest....or be stabbed in the chest with a knife through a t-shirt? Which do you think you stand more chance of surviving, the kinetic energy or the penetration?

The .357mag has up to 700ft.lbs of kinetic energy that's ALL deposited right on your chest....the knife about 30ft.lbs that penetrates.

Anyone that tries to argue that point needs to open a few more books....preferably not of the comic variety.

Answer 5

If a bullet with alot of kinetic energy hiits you it can send shock waves throughout your body for eg if you get shot with a .50BMG in the belly button area it could explode your heart.

Answer 6

Bigger, heavier, and slower, will outkill smaller, lighter, and faster, every time. Look at it this way, would you rather be hit by a mack truck doing 55, or a Volkswagen doing 70?.

Answer 7

Bassicly when you shoot a shotgun it makes something called a Buck blast, which is pretty much like a big impact that causes major damagee when it hits something.

Also, someshotguns shoot something called a twelve gauge instead, which is pretty much like a metal ball that causes less damage but is still good.
Hope I helped!

Answer 8

no