[Cosmoline]

The more I learn about good hunting ballistics, the more I question the self-defense theory that a bullet should "dump" its energy in a target rather than penetrate through. Both the physics and biology of this theory seem HIGHLY suspect.

To kill any living thing with a bullet quickly, you have two main choices. A central nervous system hit will kill almost instantly, but is extremely difficult and risky. The only game I know of where it's done on a regular basis are elephants, which move slowly and have (relatively) large brains.

The other option, used in 99% of kills, is to send an expanding bullet through the heart and lungs of the animal. The animal dies from the shock caused by massive blood loss, primarily through the LARGE EXIT WOUND resulting from the expanding round.

Now, there is no reason these same principles should not apply to humans. Yet instead of proper hunting ballistics, the self-defense crowd advocates bullets that DO NOT penetrate all the way. The seem to think it's preferable to use SP bullets with low sectional densities fired at low velocities. When they hit the target, the noses expand, and then promptly stop the bullet like an air-brake. It does not cut a large exit wound, and in fact it is seen as dangerous if it does go through. The target consequently may not be incapacitated by massive shock. Internal bleeding will occurr, but unless the heart or a major artery is hit, it may take some time to stop the person.

The notion that the dumped "energy" of a big fat slug is going to do anything to the target is absurd. The level of ft. lbs. may look high, but in reality the human body can take a lot more raw energy than that. Bullets do not do thier damage because of "energy."

I am willing to bet whatever money you care to put down that any of my hunting rifles, even my antiquated 1891 Argentine Mauser, loaded properly, will work far, far better at self-defense than of the "energy dump" handguns or carbines. Get hit with a proper bullet from a full-size centerfire hunting cartridge in the torso or head and you will never, ever get up again. The same cannot be said for typical self defense pistol rounds.

[GunNut]

The other option, used in 99% of kills, is to send an expanding bullet through the heart and lungs of the animal. The animal dies from the shock caused by massive blood loss, primarily through the LARGE EXIT WOUND resulting from the expanding round.

I think the animal dies by the holes in the heart/lungs/arteries that the shock and bullet fragments create. The LARGE EXIT WOUND only allows a place for the blood to exit, making tracking possible, and is only created because of the extremely high velocity.

It's really hard to compare a 150gr .308 bullet travelling at around 2500fps, with a 125gr 9mm bullet at 1100-1200fps. A rifle with the proper bullet and adequate placement will ALWAYS be better than a handgun.

Thus, the reason to use your handgun to get back to you rifle/shotgun.

Handguns definitely are not the most effective weapon, but try sticking your hunting rifle in your waist band and walking around town.....:neener: boy would that be a sight.

Steve

[Cosmoline]

The LARGE EXIT WOUND only allows a place for the blood to exit, making tracking possible, and is only created because of the extremely high velocity."

It's the blood loss that kills. The holes in the organs is only important because it allows the blood to flow. This is a technical but very important point. To stop a living thing quickly, you must create a large exit wound. Otherwise blood will simply pool up and kill more slowly.

Of course, I agree that it's often not possible to carry a rifle around. What angers me is the line of thinking, found in many handgun mags and among certain self-defense writers, that a handgun is actually BETTER. I also object to the bogus argument that the "dumped energy" makes certain poorly-performing bullets somehow work better.

And it is possible to get large exit wounds with a handgun. A .44 Mag with a good bullet can certainly do it.

[ojibweindian]

I agree with Cosmoline; "energy dump" is highly suspect. The variables involved in estimating one-shot-stop percentages are to numerous to give any real definitive estimate to a cartridge's effectiveness.

BTW, has anyone ever factored in PAIN felt by BGs in OSS calculations? Surely tolerance to pain has some effect.

[curt]

I've always thought of the concept of dumping energy to be a bullet which is of sufficient diameter to ensure that all of the available enery is used to break/smash/tear stuff. If you have a round exit the body then there was obviously energy that was not converted to work inside the target which equates to a loss of efficiency and since a pistol round doesn't have much oomph to begin with a loss of effciency in transferring its energy to ripping flesh is bad.

I don't know jack about hunting but i wouldn't think that the lack of an exit wound would be that big a deal. It seems that the circulatory system runs with enough preasure that a hole in the pump or a major pipe is going to reduce flow sufficiently regardless of whether the blood goes outside or inside. I do of course see the point about tracking that GunNut mentions. People die from little bullet holes with no exit every day.

[GunNut]

It kind of seems like we are trying to argue effectiveness vs. practicality.

In a hunting situation it is desired to have a large exit wound, to better use the power and capabilities of a hunting bullet.

Were we to use the same principals in a self defense handgun, we would also put innocent bystanders into harms way.

The self defense handgun bullets is designed to penetrate 10-12" and leave all of its energy inside its intended target.

I don't believe that any of us would argue the effectiveness of a hunting rifle and bullet on a human or animal target.

But like I said, they are not appropriate where innocents could be hit.

If given the choice of going to war with a rifle firing sp or hp ammo, or a handgun.......I'm pretty sure we would go with the rifle, but collaterall damage is acceptable in war.

Steve

[Cosmoline]

That's another one of my Sunday rant topics :D

I can understand the concern, in theory. However, these concerns can be eleviated by using a bullet that, while creating a proper exit wound, will not retain much of its mass in the process. Small, high-speed projectiles with thin jackets and a low sectional density might do nicely.

I also feel strongly that many more innocents have been put in danger by missed shots from small handgun cartridges than ever would have been put at risk by use of proper long guns with proper full-power cartridges. But that's probably another rant.

[Zak Smith]

Exit wound?

If a hunting bullet penetrates the heart/lung area and comes to rest under the far side skin with no exit wound, the animal will still bleed internally - the same effective blood (and pressure) loss. From deer hunting, the result I've seen, even with an exit wound is that the lungs fill up with blood, then it starts spilling out the hole.

-z

[DigMe]

I'm no expert on the physics of all this so I can't really pretend to present any great scientific argument, but just speaking from experience...I've shot some BIGA$$ feral hogs in the wild with 12 gauge 00 magnum loads and a Ruger .223 ranch rifle. I also witnessed a friend of mine take down two equally large feral hogs with a .22 magnum rifle. Because of the size of a hog and the thickness of hide and whatnot none of these shots resulted in an exit wound. However in every single case the hog went down IMMEDIATELY and appeared to be fully dead within a minute. Again that's without exit wounds. These central Texas feral hogs live in rugged country and are notoriously tough (actually central TX has nothing to do with it I guess). Yeah, I suppose a large exit wound gives the blood an external place to go but I feel that near equal if not equal devestation CAN be done with the right load and no exit wound. Can handguns below .357 magnum generate that kind of devestation? Well that's a whole other argument!

On a side note I hope to purchase a .44 mag at some point and start open-sight hunting hogs with that exclusively. It'll be a while though as I'm a lowly social worker about to get married. :banghead:

brad cook

[Keith]

The whole concept is a bit silly.

A bullet that goes THROUGH a target "dumps energy" all the way through as it breaks through bone, meat, etc. A bullet that stops within the target would dump less "energy" since it cuts through less tissue and encounters less resistance.

There are sound reasons for wanting a hunting bullet to exit, and a defense bullet to stay within the target, but the energy thing doesn't make any sense.

Keith

[Cosmoline]

Good points about bleeding out into the lungs, esp. on larger animals with big lungs. Of course this will produce shock and death as well. My point was that there is no "energy" being "dumped" into the target when a bullet doesn't penetrate all the way. The hog doesn't die because it's been hit with X ft. lbs. of "energy" that would have been lost if the bullet penetrated through. That's obvious. Yet the proponents of "energy dumping" want us to believe otherwise.

[444]

I have to agree. For the energy dump theory to make sense to me, you would have to be talking about two bullets with the same energy to begin with. For example, let's say we are talking about using a hollow point bullet and a FMJ bullet both of the same weight and fired at the same velocity. If the hollow point expands and expends all it's energy in the target and the FMJ just punches a nice small hole all the way though, then we might have an argument. But, if we have two different calibers with one being significantly more potent than the other one, and one stops in the body and the other one goes all the way through, then it seems to me that the more powerful cartridge may have dumped a similar amount of energy and still had enough additional energy to also exit the target.

Another factor is that in most of the examples cited so far, we have been talking about a "good" shot. A shot through the vitals. Putting a hole though an animals heart and/or lungs is probably going to kill the target whether or not you have an exit wound. But on a more marginal shot, it might make a difference. The internal bleeding has to go somewhere. If it can't exit the body, an argument might be made that it may tamponade the flow of blood because it is exerting pressure against the wound. Or possibly if the blood begins to pool, it can clot. If there is an exit wound, I would believe that it would tend to keep the blood flowing. Then we get into thoracic injuries such as pneumothorax and tension pneumothorax. This would be the classic sucking chest wound. When an animal inhales, the diaphram flattens out creating a vacume in the chest cavity. Normally this causes air to enter the lungs through the trachea. If you have a hole in your chest, this same action results in air entering the chest through the holes. As this air builds up inside the chest, it compresses the lungs creating a life threatening situation in and of itself. And, if you have more than one hole, more air will enter the chest faster.

[popbang]

I believe there is a bigger problem with the concept of energy dump. Quite simply it isn’t there. By that, I am talking about the energy. An example is I take a steel spinning target and shoot it with a 230-grain hollow point traveling at an average of 920 fps. Now the target weighs about 4 pounds and the bullet is producing about 430 foot pounds of kinetic energy. And you know what it spins the target a couple of times but nowhere near what it does if I hit with a 32-ounce hammer. So, what happens to this supposed energy? I took a piece of wood that weighed about 62 pounds and fired into it the bullet did not exit, but guess what the stump didn’t move. Again, with the energy produce it should have moved about 7 feet. I put a steel plate on the piece of wood and shot it again. Still nothing. The energy transferred by a handgun bullet is closer to the momentum value, around a pound.

In the end I believe the bullet characteristics are much more important than the energy of a load. If the bullet consistently expands and goes 10-14 inches in gelatin I believe that is more important than energy.

[Andrew Wyatt]

It's the blood loss that kills. The holes in the organs is only important because it allows the blood to flow.


even if i had a magic bullet that left no entry or exit wounds but still left holes in organs, the target of said bullet would still die.


if i had another magic bullet that left cauterized holes in the skin, and no holes in the organs, the target would not die.

[zahc]

IME if you put a hole thru any animals lungS, that animal is dead. That wound is unsurvivable. And lungs are big.

[Cosmoline]

If you had an animal that did not use pressurized blood to move oxygen to its cells, putting little holes through it would have no great effect. The little holes made by bullets only kill so well because they cause a massive and sudden drop in the blood pressure resulting in shock, and it's this shock that kills. The hole itself is just a hole. If the hole only cuts through muscle and bone, the wound will only be fatal if the blood flow can't be stopped or if there's an infection. Lung shots kill because the blood flows freely into the lungs and again you have a drop in pressure and shock. If you make a hole in the lungs and manage to miss all the vital arteries around the lungs, you will just create a sucking chest wound and death will not always come very quickly. Certainly it's better if you hit both the heart and the lungs, and have a nice exit wound. That sort of a wound is basically 100% fatal and in short order. Whether it's a squirrel or T-Rex, it's going to crash and die.

[Andrew Wyatt]

uuh, even if i was shooting at robots, the more damage dealt to internal organs the better.


that's the whole point of expanding ammo.

[P95Carry]

''Energy dump'' is rather an unfortunate term .... ''energy expenditure'' sounds better!

For me, the whole deal is about damage ... to tissues ..... bullet design and thence performance will make a considerable difference to the nature of that damage but surely the bottom line is ...... a bullet carries ''x'' much kinetic energy .... this being a function of velocity and mass. This represents an ability to ''do work'' ..... viz, tissue damage.

I have to say .. if a bullet penetrates and then exits ..... it must perforce still have energy remaining ... arguably that could be seen as energy not usefully used within the target to produce more tissue damage. A factor often levelled at ball ammo.

The handgun deal is very much geared to minimizing over penetration, to avoid third party injuries .. a specific case.

The delivery of the available energy is going to we hope produce both tissue damage - AND shock. The latter is in part a function of reduced blood pressure following blood loss but .... we must also remember that when gross tissue damage occurs there is also the release of other chemicals .. instance histamine, 5HT (5hydroxytriptamine) ..... both potent when in sufficient quantity .... and themselves able to effect a drop in blood pressure.

The ''magic'' CNS hit is far too hard to achieve to place much reliance on so .... invariably we have to deal with massive body cavity damage and blood loss.

The expanding bullet that uses all its energy in creating damage surely makes best use of that energy .. no exit ... just huge tissue disruption (including hydraulic effects as well as fragmentary).

Wound science is a big subject .. and contains much contention but.... for me, the fully expenditure of a bullet's energy is more useful than less.

[ShaiVong]

Whats all this about without an exit wound it cant bleed externally? What about the hole the bullet punched when it ENTERED the animal?

[ShaiVong]

I believe there is a bigger problem with the concept of energy dump. Quite simply it isn’t there. By that, I am talking about the energy. An example is I take a steel spinning target and shoot it with a 230-grain hollow point traveling at an average of 920 fps. Now the target weighs about 4 pounds and the bullet is producing about 430 foot pounds of kinetic energy. And you know what it spins the target a couple of times but nowhere near what it does if I hit with a 32-ounce hammer. So, what happens to this supposed energy? I took a piece of wood that weighed about 62 pounds and fired into it the bullet did not exit, but guess what the stump didn’t move. Again, with the energy produce it should have moved about 7 feet. I put a steel plate on the piece of wood and shot it again. Still nothing. The energy transferred by a handgun bullet is closer to the momentum value, around a pound.

I think you might have missed the point..

With the spinning target, the only energy being dumped is the ammount of energy required to torque the target, which is low. Unfortunately you deflect the bullet at the same time, and this isnt a complete energy transfer. If you could shoot a spinning target with a bullet that would expend most of its energy upon the target (maybe if it was putty rather than lead) then i assure you it would spin much faster than a hammer hit.


With the block of wood, all the energy is expended in deformation and heat generation. Even if you used a sledgehammer to produce the same ammount of newtons as a lighter bullet with a greater velocity, it wouldnt penetrate nearly as much as the bullet, but you could wail that piece of wood a long way, because there would be a velocity transferrence, rather than much deformation and heat. F=MA. F being Sigma, sum of, F.

[redneck]

Your leaving out a big section of hunting....varmint hunting. Here you have bullets that expand explosively expending large amounts of energy over a fraction of a second. The animal is blown to peices. That kills much quicker than a heart shot with a solid, exit wound or no.
Granted, you can't get enough kinetic energy to do that to a human sized critter, especially out of a handgun. But the idea seems to be the same to me. If the bullet expands enough to stay inside, it may break apart and do damage in multiple directions, or it might just turn everything into goo. Energy is conserved, if the bullet starts off with X ft-lbs of kinetic energy, and ends up with zero ft-lbs of energy, then X ft-lbs of energy was expended doing something. In this case, squashing stuff.
You do as much internal damage as possible, without the added risk of the bullet retaining enough energy to hurt somebody after blowing clear through the intended target.
The energy dump isn't intended to "knock them over" its to do as much internal damage as possible without sending the bullet to places unknown. Internal bleeding isn't any better for ya than external bleeding.

[goalie]

Just my 2 cents, but, as a nurse in a big, inner city hospital I have seen quite a few GSWs. Either you hit the brain/spine and they drop or you hit the heart and they bleed out relatively quick. I have seen people shot in the chest with a .45 APC and be ambulatory and I have seen people dropped with one well placed .25 round to the chest that hit the spine. A lot of the caliber debate is kind of ridiculous IMO, simply because proper shot placement is the key to stopping anyone or any critter where the foot pounds of energy transferred is not exponentially higher than the critter/person's body weight.

[Mizzoutiger]

Sounds to me like everyone can agree that SHOT PLACEMENT is key. ;)

[ShaiVong]

Yep, definately the key.


What about the 223 ball ammo that fragments when it enters tissue over a certain velocity? That usually doesnt create an exit wound, but its mighty effective.

[cratz2]

The thing I've never completely believed is for the 'energy dump' crowd, by definition, they believe that if two identical targets were shot with two identical bullets, say controlled expansion bullets such Barnes X-Bullets in 308, that if in one target, the bullet hit one additional bone or was at an additional 5 degrees angle and didn't exit, the animal is going to just flop over dear whereas if that additional bone or angle isn't met, and the bullet passes through, the animal is going to lead a long a prosperous life.

Take a .30 cal 150 Gr X-Bullet at 2,800 fps. Shot into one lung and passes through the other lung taking out at least one rib. If everything goes perfectly to plan, the bullet will expand to about .45 cal by exit and will travel only a few yards after exiting. Most of the energy is deposited into the animal but an exit wound is consistantly left. How far does the deer go?

On the other realistic extreme, we would have a 75 Gr VMax bullet in 243. If all goes as designed, the bullet will penetrate a short distance unless it encounters a rib straight on. A shot into a deer should still get 6" penetration at minimum, again barring a rib hit, and that would include the near side lung of the shot was so placed. How many here really think that the deer would expire within 100 yards of the shot or so? I sure don't

I buy into Randy Brooks belief that in a big game bullet, if it doesn't completely exit from pretty much any realistic angle, the bullet failed. Controlled expansion is what I want in an animal that weighs over, say, 100 lbs. On the other hand, I've seen the devastation that results in an energy dump bullet such as a 40 to 50 Gr VMax at 2,500+ fps. The only word that comes to mind is explosive. Either feathers everywhere and very little meat left, or a massive crater of a wound just inside the entrance on something like a coyote. But to expand that up to the scale required for a 200 lb deer, we'd be talking about one big bullet at an extremely high velocity. And then we'd still see massive meat damage, the pelt would be gone etc...

And that still doesn't explain how a coyote would be nearly immediately incapacitated from a heart or lung shot from a .270 with enough weight to almost ensure no expansion took place? Or how a 160 lb deer hit with a 338 Win Mag flops over dead within seconds.

Maybe I'm oversimplifying it by only looking at the extremes but I don't think so. Using pure logic, you must look at extremes when arguing two opposing points. In the real world, if you put a bullet with adequate penetration, be it a Nosler Partition, VMax with some weight to it or a Winchester PowerPoint, through the heart and at least one lung of a 150 to 200 lb deer, it is more than likely going to die soon enough to be recovered. This is whether you are using a .243 that doesn't completely penetrate or using a .45-70 that completely penetrates the deer and then penetrates 4 feet into the ground.

Controlled expansion of an appropriately sized and weighted bullet with adequate penetration that leaves an exit wound is ideal. In my book anyway. ;)

[Oracle]

IMHO, the "energy" of a round that does not cause hydrostatic shock (i.e. handgun cartridges) only facilitates the damage of tissues by the crushing and cutting action of the bullet as it travels through those tissues. Expanding bullets are good because they open up to a larger size, and thus cut, crush, and injure more tissues as they move through the body.

Really, it doesn't matter if a bullet exits the body or not. It matters whether it has injured enough tissues to cause the person (or animal) to either stop their attack or drop (in the case of hunting). Shot placement is the most important thing, as this determines whether the tissues the bullet is injuring are vital and will cause immediate cessation of activity, or not.

Hydrostatic shock in humans and animals only comes into play with bullets going very fast, and it only causes damage when the temporary stretch cavity caused by the hydrostatic shock exceeds the stretch capacity of the organs affected, causing injury through tearing. This is why prairie blow up when hit by a high-velocity round within a certain range, the temporary stretch cavity caused by the hydrostatic shock is larger than the stretch capacity of the prairie dog's body. Thus, it blows up.

[Preacherman]

I agree with those who've pointed out that in a self-defence situation, over-penetration is undesirable due to the risk to innocent bystanders, whereas in hunting, an exit wound takes on new advantages. However, I think that the vital point has not yet been made.

Energy is defined as "the capacity to do work". This is why it's defined in foot-pounds: a foot-pound of energy is that amount of energy sufficient to move one pound of weight a distance of one foot (ignoring the effects of gravity, friction, etc.). So, in theory, more energy = greater work capacity, right? Well, it doesn't work out that way with bullets...

Peter Capstick gives a good example of this with his description of a buffalo hunt in Africa. This particular buffalo was socked with a .460 Weatherby Magnum - TEN TIMES! He continued running along until the last couple of shots, when he finally expired. All of the shots were well aimed, and all performed as expected (when examined, the buffalo's chest cavity - heart, lungs, etc - was shredded into ribbons). It took a total of over 60,000 foot-pounds of energy to put that buffalo down! Was this a failure? No - just that the buffalo hadn't read the ballistics charts, and didn't want to give up! I've also seen buffalo shot once with a .375 H&H, and go down almost immediately (I've done this myself three times). Does this make the .375 H&H a "more powerful" or "more effective" or "superior" cartridge to the .460 Weatherby Magnum? Not in the least!

The energy of a particular round is a nice ballistics figure, and has its place: but energy is only the capacity to do work. The target, on the other hand, has the capacity (to a greater or lesser extent) to resist the effects of that work. If you shoot a buffalo (or deer, or bear, or ...) that doesn't know you're there, and is not charged up with an adrenalin dump, the bullet is much more likely to take effect quickly. On the other hand, if that animal is alert, and scared, and running, the adrenaline dump is having its full effect, and doing the same amount of work to the animal will take much longer to have an effect.

The same applies to self-defence situations. We've all read the horror stories about criminals who were hopped-up on a cocktail of narcotics, alcohol and adrenaline, and who absorb an uncanny amount of damage before going down. There's the Chicago druggie who was shot 18 times with handgun rounds, and still kept shooting - it took two shotgun slugs (one to the head) to end his criminal career. There's the New York case of the hopped-up restaurant robber who was shot 18 times with .38 Special +P 125gr. JHP, and just stood there throughout the shooting (including two reloads), not moving, not falling down... at the autopsy, they reckoned his blood was orange and fizzing! The energy these guys absorbed was more than enough (in theory) to kill them (and in fact did kill them, after a time): but it was not sufficient to stop them. Was this an "energy failure"? No, not at all... just that they could absorb that energy better than the average target. (Makes one more aware of the value of a good central-nervous-system shot, too!)

[curt]

... at the autopsy, they reckoned his blood was orange and fizzing!

Those Orange Crush addicts are the worst.

[Oleg Volk]

Energy does work...but does it work to deform tissue and bone or just to deform the bullet itself? Is KE wasted mostly on deforming the projectile?

[Frohickey]

Another reason for wanting a bullet to go all the way through instead of lodging inside the bad guy... bad guys don't like the good guys to be digging out the bullet with their Leatherman tool without anesthesia. :D

In all seriousness, the amount of energy in normal pistol or rifle calibers do not do the damage to tissue. Its the use of that energy to crush tissue, bone and organs that does the damage. So, ideally, you want the bullet to just poke out of the other side of the skin, this way, all of the energy was used to crush tissue, instead of going outside. to crush the drywall and the pet cat.

Since you can't predetermine the bulletpath, you are stuck with 'guessing' as to how much energy to give the slug in order to go through as much bad guy tissue/bone as possible, without giving the good guy more recoil than is required. This is how they got to the 12-14 inches of tissue simulant penetration.

As said earlier, energy is used to crush tissue/bone, but the other part of crushing tissue/bone is the slug itself. If you don't have enough energy to drive the slug into bad guy body parts, you dont' have enough tissue damage.

[Oracle]

Oleg,

I don't think that KE is wasted on deforming the bullet, if the bullet deforms in a way that makes it crush and deform tissue and bone more effectively. In other words, the energy necessary to make a good HP bullet open up isn't wasted if thereby more tissues are disrupted by the increased diameter of the expanded bullet.

[ShaiVong]

What about the temporary cavity and shockwave created by the bullet entering? Is that the hydrostatic shock that The Oracle was talking about?

Hey. Is that your site oracle? :uhoh:

Ammo Oracle! (http://www.ammo-oracle.com/#fbispec)

[Penforhire]

It can't be all about penetration. Otherwise the difference between 45 caliber bullets and, say, 38 Spec. would not be significant. You'd either strike something vital or you wouldn't.

Some people have said that a spinal hit (CNS) often causes instant stops. Maybe a fragmenting or deforming bullet stands a greater chance of damaging something vital than a straight throuth-and-through. I liked the analogy to varmint rifle rounds. I think people are closer to varmints than they are to elephants and bears. We don't have that much armor.

I was just reading Speer's reloading manual and they noted that Gold Dot bullets were designed to expand but also survive some penetration (cover) also. Those needs do sound like competing qualities.

Above some velocity there is a temporary cavity formed that sounds like serious shock damage to me. How about a round that can cause a huge temp. cavity but not endanger when it overpenetrates (as a shotgun slug would). Anyone for really high velocity shotshell ammo?

[Frohickey]

Temporary cavities are irrelevant. Unless its permanent, you can't count on its wounding effects.

Permanent cavities are what is important, and it encompasses the permanent effects of the projectile, including any tearing/damage the shock impulse would do against the relatively elastic tissues.

What makes temporary cavities permanent is if the animal is smaller in size than the size of the temporary cavity. Thats why the hot 220Swift has 'explosive' effects against squirrels and ground hogs, while it makes for nasty shallow wounds on larger animals.

I wonder what the size temporary cavity is made by those depleted uranium fin-stabilized 120mm rounds. If its larger than a man, then you can say 'pink mist'. :uhoh:

[benEzra]

I generally stay out of these discussions because I don't like to get flamed, but I am a strong advocate of kinetic energy and moderate penetration vs. momentum and deep penetration/overpenetration. You guys that like momentum/deep penetration, more power to you, and certainly choose what you are confident with. But please remember that rational people CAN disagree with you (and with Fackler et al.), and those of us who do favor light/fast/early fragmentation, or who believe that temporary cavity isn't necessarilly irrelevant, aren't necessarily idiots or ignoramuses. This is a complex subject, and there are good arguments on both sides.
I take a steel spinning target and shoot it with a 230-grain hollow point traveling at an average of 920 fps. Now the target weighs about 4 pounds and the bullet is producing about 430 foot pounds of kinetic energy. And you know what it spins the target a couple of times but nowhere near what it does if I hit with a 32-ounce hammer.
What spins the plate is the momentum of the bullet, not the energy. Shoot the plate with a 40-gr JHP out of a .223 and the plate probably won't spin any harder than if it were hit with a .45, but you will get a crater in the steel. Momentum moves the target, while energy deforms the target.

[Ledbetter]

Redneck said it best:

if the bullet starts off with X ft-lbs of kinetic energy, and ends up with zero ft-lbs of energy, then X ft-lbs of energy was expended doing something. In this case, squashing stuff.
You do as much internal damage as possible, without the added risk of the bullet retaining enough energy to hurt somebody after blowing clear through the intended target.
The energy dump isn't intended to "knock them over" its to do as much internal damage as possible without sending the bullet to places unknown. Internal bleeding isn't any better for ya than external bleeding.

Me: An exit wound is not at all necessary for massive bleeding to occur, especially if the aorta or other large vessel is even nicked.

I add this: A bullet traveling through a body in a straight line will do less damage than one that corkscrews or arcs through, or creates multiple wound channels.

I also state: Waiting for a broadside shot through both lungs is an easier proposition when you're hunting than when you're defending against an aggressor that bleeds orange fizzy stuff.

[Cosmoline]

If a big fat bullet stopping in a target was preferable to a thin, long bullet piercing through, why don't we see low-SD bullets being used against big game? Granted a bullet may still kill an animal even if it doesn't create a large exit wound, but I've never heard anyone argue that the bullet is doing MORE damage by stopping in the target and somehow "dumping" its energy.

It's not a question of favoring "momentum" over "energy." It's much more basic than that. Bullets typically kill by tearing big holes that cause a dramatic drop in blood pressure. Either that or you get lucky and hit the central nervous system. Those are the ways to kill quickly. Other ways will kill more slowly, but obviously those should not be the first choice in a time of need.

What I propose is bringing the hard-earned lessons of hunting into the field of self defense. If nothing else, it might cut down on the bravo sierra that seems to overflow from the handgun magazine gurus.

I don't think there's much disagreement when you boil it down. It may be a matter of what terms are being used.

[Ledbetter]

Because it ruins the meat.

Don't know about the legality. Anyone?

[Frohickey]

If a big fat bullet stopping in a target was preferable to a thin, long bullet piercing through, why don't we see low-SD bullets being used against big game?

Some are, but generally, they are used by handgun hunters because you are not going to get a lot of retained velocity at long distances.

Best bullet for tissue damage is a bullet with sharp edges, which means a cylinder (wadcutter). In all types of actions, its easier to chamber a round when its rounded a little bit. More if the cartridge case is too (bottleneck).

For a semi-auto pistol for self defense, you'd have to settle for a bullet that reliably chambers and ejects. I've seen some 1911s/Glocks that are do not chamber with semi-wadcutters, or fails to eject properly when the next round is a semi-wadcutter.

For a revolver, it would be difficult to speedload wadcutter rounds, as now, you have 5/6 rounds to properly align.

Cast Performance's LBT product line is pretty aggressive as far as wide meplats (flat part of the tip of the bullet). Here is what Garrett Cartridges (http://www.garrettcartridges.com/420.asp) have to say about wide meplats.


About temporary cavities and energy, I'm just reading through Duncan MacPherson's book 'Bullet Penetration' (http://pw1.netcom.com/~dmacp/Fackler_review.html), and he makes a valid point that unless the temporary cavity made exceeds the elastic limit of the tissue, you are just moving the tissue aside, and its going to go back where it was afterwards. If the temporary cavity exceeds the tissue limit, then it just became the permanent cavity. If the temporary cavity is bigger than the tissue itself, this is just another variant of the temporary cavity exceeding the tissue limit.

[redneck]

Can't always pick your shot on big game. All the accounts of african hunts for stuff like buffalo I've read, involved using an expanding bullet for the first shot, and solids to follow. First shot, you go for the vitals, and do as much damage as possible. Follow ups are usually whatever is presented, if thats the south end of a north bound buffalo you need quite a bit of penetration to put the bullet through the vitals, which goes back to shot placement. The bullet has to get there before you worry about expanding, non expanding, exit wound or no etc.

[Oracle]

I think the reason that expanding SD ammo isn't used much on game is that it doesn't penetrate enough to disrupt the vital tissues in many game animals. Remember, humans are fairly thin skinned, and our sectional density isn't as great as many others in the animal kingdom. Thus, what may be adequate penetration to disrupt our vital structures may not be on game animals.

This is also why I'm not in favor of very light, fast handgun projectiles that break up upon impact. The wounds that they do are very wide (large) but very shallow, and don't usually penetrate enough to disrupt vital structures in the human body. Unless you hit someone just right, then that large wound isn't going to cause enough shock to incapacitate them, especially if they are wearing heavy clothing and/or they put something in the way of your shot, like an arm. I prefer to use a round that expands to at least .60 caliber and penetrates 14-16 inches in ballistic gelatin. Those seem to be the "magic numbers" that ensure a fairly reliable stop when fired into the center of mass. Ultrafast, ultralight projectiles such as the new zinc and aluminum bullets that are coming out now many times don't even penetrate 6 inches in ballistic gelatin, that's less than half my criteria for penetration. But, hey, everyone is free to make their own choices, I've done my research and chosen what I prefer to carry, and everyone else is free to do the same.

[ShaiVong]

Ahh my friends! Its all about VOLUME! If one bullet wont do, try 50!:evil:

[QKRTHNU]

If the energy "Dump" was really the lethal element than Soft Armor wouldn't be of any use.

All of the energy is dumped when a vest is struck.

A bullet is not a bludgeoning weapon.

[Bonker]

Oh THAT kind of energy dump! I thought this thread was about what happens when I eat too much bran and power bars :)

[benEzra]

If the energy "Dump" was really the lethal element than Soft Armor wouldn't be of any use.
All of the energy is dumped when a vest is struck.
The energy is absorbed by THE FIBERS OF THE VEST AS THEY BREAK, not the body of the wearer. It takes a LOT of energy to stretch and break a fiber of Kevlar or Spectra, and each of the hundreds or thousands of fibers that break upon impact absorbs that much energy from the bullet.

The wearer of the vest gets the momentum, but almost NONE of the energy (just enough to leave a big bruise).

In the case of hard armor (i.e., level IV external armor), the energy is dumped into the ceramic plate, progressively fracturing it and grinding the fragments into powder, while also grinding away the nose of the bullet.

[George Hill]

Energy Dump... That's pumping out 30 rounds from an AK as fast as you can.

[444]

That is making a lot of noise.
Hitting something is energy dump.:neener:

[QKRTHNU]

The energy is absorbed by THE FIBERS OF THE VEST AS THEY BREAK,
Duh, that's what I get for posting without thinking.

Make that solid armor (non-ceramic). You wouldn't get knocked down.;)

[ShaiVong]

I just wear another layer of flannel.:neener:

[Frohickey]

Flesh/tissue is mostly water. You need 4186 Joules of energy to raise 2.2lbs of water by 1degree celsius in temperature.

A 230gr bullet going at 880FPS has 536 joules of energy (396ftlbs)!

Assuming that you have an infinitesmally small bullet, say the size of an atom with the same energy as a 230gr bullet going at 880fps, aside from poking a small hole, and heating up some tissues, and maybe causing some individual cells DNA damage, the person is still going to be alive after being hit. Heck, hit them with a gazillion of these and maybe their hair will fall out after a week.

[New_comer]

The bullet's energy is supposed to help it crush, slice, dice, and break up tissue to be effective.

If the slug merely slides and slithers effortlessly through tissue and skin, it'd only give the BG a couple of very large sweat pores - a dramatic display of firepower, resulting to a useless acupuncture.

Translating energy to tissue destruction to effect bleeding requires proper bullet design. But, basic assumptions must be accepted: as in flat-end projectiles crush more rather than slither thru, that larger diameter slugs have greater chances to strike vital tissue, that the deformed metal edges of the peeled jacket slice even more tissue adding to the injury and so on. So, if most of the available energy is converted to the crushing and cutting of tissue, chances are better that the BG will cease hostile activity.

But, if the handgun bullet could be propelled to such speed that even in its rounded form, it still could crush the tough tissues and arteries to effect bleeding by mere mass displacement and impulse, then hollow points would have seen the last of its days.

Until then, I'd always marvel at the spectacle of 'energy dump' of JHP's and exotic bullets stopping those fanatical gelatin and clay blocks. :eek: :evil: :D

[benEzra]

unless the temporary cavity made exceeds the elastic limit of the tissue, you are just moving the tissue aside, and its going to go back where it was afterwards. If the temporary cavity exceeds the tissue limit, then it just became the permanent cavity. If the temporary cavity is bigger than the tissue itself, this is just another variant of the temporary cavity exceeding the tissue limit.
Entirely true. The one thing that I think Fackler et al miss, however, is that tissue is a composite, and the elastic limit for one component of said tissue is different from that of other parts. Nerves, for example, are extremely fragile (ever bumped your elbow where the "funny bone" nerve passes through?) and their functional elastic limit is quite low at the microscopic level, whereas that of the connective tissue surrounding them is quite high. Dilated blood vessels are quite fragile (hence the danger of transecting your descending aorta by falling off a low roof and landing on your side), and it has been shown (Ragsdale et al., Armed Forces Institute of Pathology) that a pig aorta embedded in ballistic gelatin can be transected by the stretch cavity even if the surrounding gelatin is undamaged (i.e., outside the permanent cavity). Hence, a large temporary cavity can conceivably act to stun nerve ganglia, make muscles unusable (ever pulled a muscle? ever pulled one to twice its normal max length??), activate artery and arteriole stretch reflexes that cause a massive drop in blood pressure (by artery relaxation), and a whole host of other factors that could contribute to a "stop." Meanwhile, the large stretch cavity may allow a couple inches leeway in shot placement, in that a blood vessel just outside the permanent cavity might still be transected.
Assuming that you have an infinitesmally small bullet, say the size of an atom with the same energy as a 230gr bullet going at 880fps, aside from poking a small hole, and heating up some tissues, and maybe causing some individual cells DNA damage, the person is still going to be alive after being hit. Heck, hit them with a gazillion of these and maybe their hair will fall out after a week.
Actually, the lethal whole-body dose from gamma radiation, translated into joules, is the same order of magnitude as the KE of a handgun bullet.
500 rem = 500 rad (for gamma rays) = 5 J/kg body mass, so
75 kg person * 5 J/kg = 375 J = 277 ft-lb
(Fun fact for the day.)

[griz]

Well to get back to the original rant, comparing hunting bullets (rifles) to self defense bullets (handguns) is an apples to oranges comparison. Actually a closer analogy would be cantaloupes to oranges. For most game, rifles have energy to spare and can thus use the surplus to plow through the extra obstructions game animals present. Animals are usually horizontal and thus have shoulders and mid-sections that can get in the way, people are vertical and generally don’t have as much obstructing areas.

For a true comparison, look at FMJ pistol bullets versus JHP. For normal SD calibers, JHP bullets are acknowledged to be more effective than FMJ, even though the JHP may likely not exit. The effectiveness isn’t based on an exit wound, it’s on how much of the important equipment inside is torn up.