why isnt two holes better than one?

[Richardson]

Kinetic Energy = 1/2 mass * velocity^2

Thank you.... my blunder (trust me, I'm even better at blundering than at engineering).....

 

[NMshooter]

Less difference between FMJ and your favorite JHP than most folks realize.

If you want a one shot stop you still have to shoot them through the brain.

That said, I do prefer JHP ammunition, and it does give you a slight edge.

Just do not think that expanded diameter is so important that you trade penetration sufficient to actually damage important stuff for it.

 

[MTMilitiaman]

I think hydrostatic shock, or hydrodynamic impulse, or whatever you want to call it, is over rated. You can be certain something of the sort exists and can demonstrate this shooting water bottles and such, but this does not demonstrate its affect on actual tissue--so it is pretty meaningless. Living tissue is pretty resiliant and elastic. Forces that tear apart fruit or plastic jugs may do little or no permanent damage to vital organs.

Especially regarding handguns, I think it is foolish to rely on this effect. Handguns are unlikely to produce the velocity required to fully produce this effect in living tissue. Thus the only thing that matters is permanent wound channel--which is the diameter of the bullet and the depth it penetrates.

Over penetration is likewise grossly over rated. The FBI studies shootings every year. I recently read a paper published by them on the mechanics of handgun wounding and effectiveness in which they stressed injury of innocent bystanders and collateral damage due to over penetration is largely over rated compared to the risks of under penetration, which, the author emphasized, gets people killed. This is why the FBI requires a minimum of 12 inches of penetration in callibrated ballistic geletin even after penetrating barriers like windsheild glass and 20 gauge steel. Regardless of how dramatic the wound looks, if it can't reach 12 inches or more, preferrebly 14, it won't be used. For me, expansion and shock is nice, but not something to be relied on. I tend to carry moderate to heavy for caliber bullets in just about everything. I carry bullets designed to exhibit the kind of expansion I feel is necessary for a given task, but even if my bullet doesn't expand, I know it will reach the vitals. This is far more important to me than having a bullet expand dramatically, but fail to reach and destroy vital organs--a small hole through the heart and lungs is better than no hole at all.

 

[RandyB]

It isn't the blood leaking onto the ground that kills you, it is the loss of blood from where it is supposed to be inside your body. A non-expanding bullet like an FMJ will usually pass through causing two exterior holes and leak paths. However they generally don't do as much damage to the internal tissue that causes blood loss and shock. Several times I have shot deer that had almost no external bleeding but the chest cavity was full of blood. The whole concept is to do damage to the muscles, organs and blood vessles inside the body, not just create a drain hole.

Right on the spot! Simple matter on cause of death its either blood loss or damage to the CNS. A FMJ is generally more lethal, it is not as effective in causing immediate death. (Fackler et al.) A great site www.tacticalforums.com is a good place to start your research on this topic.

 

[clone]

well lets try something. we will use the 45ACP in the example.

an average man is slightly over weight, so we'll say hes 24in deep.

the average JHP expands to approxmently .70,(some expand more some less) and penetrates about 14in.

FMJ most likely wont expand, and penetrates about 30in.

this is how i imagine it to happen, im willing to learn so if i'v goten some things wrong i wont feel bad if im corrected.

when the JHP enters the 24in person it doesnt expand imidiatly, so about 3 or 4 in it is still .45. then startes to expand to the size of .70. im sure it doesnt happen at once so at about 6 to 8in it would be about .60 right? and continues to expand to the .70 at 14in.

the FMJ most likely will make a .45 through and through hole breaking bone and what-not on it way through right?

it seems to me that the 24in, .45 of an inch, hole would expose more blood vessal's and have more of a chance for a CNS hit or other vital organ, than the 14in, 45. to .70 of an inch, hole.

now i know iv probably missed a few factor's so this is where the reader's knowledge or thoughts comes in.

 

[Herself]

Kinetic Energy = 1/2 mass * velocity^2

Hah! I knew the Universe was a half-massed kind of place! I just knew it!

--H

 

[WvaBill]

Waste of energy

 

[rangerruck]

it is the hydrostatic shock that will do the most damage, with the hp or exp bullets, it basically creates a shock wave in side the cavity of the body where the bullet hits, causing severe trauma to internals, even if the bullet or frag doesn't hit the organ.

 

[Soybomb]

Someone earlier in the thread said that a gun is a tool for transferring force to the target, and thats what kills. I disagree. I think a gun is a tool used to make a hole in the target, the force is just necessary to make the hole, but as long as the hole is made the measure of force is relatively unimportant.

Human tissue isn't water though and most of it compresses unlike water. Most of the ballistics "experts" agree that the permanent crush cavity is the important part of wounding, meaning expansion and penetration. Penetration being the primary wounding implement as it would stop quickest by hitting a vital organ or the central nervous system. Large wound volume from an expanded round be the secondary stopper coming from blood loss over time. Some would pick a fmj round over a jhp if the jhp can't penetrate deep enough in the caliber in question. If a jhp can penetrate deep enough it creates a wound with a larger volume for increased chances of hitting a vital area, and increased area for bleeding.

Some retailers like Extreme Shock! (insert tacticool agent picture here) would have you think that energy dump is the winning ticket. I think this is definately worth reading, it cites several other sources you can read as well. Personally I'll take fackler over blowing up watermelons in the backyard. Ymmv.

 

[LAK]

I adhere to the idea that any through and through holes are better than one in only.

Immediate incapacitation is dependent on vital nervous system tissue. Not so immediate incapacitation on a combination of tissue damage and blood loss, internal or external. A sudden sharp drop in blood pressure will have a significant incapacitating effect on most average people. The destruction or breaching of large arteries will cause the most rapid blood loss, and organs like the heart, liver etc probably the most clinical shock.

Thus my choices in hollowpoints tend to be medium to heavy, with controlled expansion and deep penetration. I do not rely on the fast opening lead parachutes that have gained so much popularity. They typically work very well on unobstructed average torso frontal targets, but lack the deep penetration when a hand/forearm etc gets in the way or angled shots on people with very large torsos etc.

And I do not see hardball as a great handicap in any caliber.
-------------------------------------------

http://ussliberty.org
http://ssunitedstates.org

 

[Ryder]

why isnt a through and through (fmj) shot from a pistol better than a expanded jhp?

An expanding bullet can easily produce a pass through shot. A little secret that apparently only us handloaders know Light and fast verses heavy and slow are not always exclusive to each other. I do tend to like heavy and fast myself.

 

[Herself]

Someone earlier in the thread said that a gun is a tool for transferring force to the target, and thats what kills. I disagree. I think a gun is a tool used to make a hole in the target, the force is just necessary to make the hole, but as long as the hole is made the measure of force is relatively unimportant.

Can't make a hole without applying force! All weapons are tools for applying force at a distance; some happen to apply it over a greater distance than others. (As a general rule, the farther away you can be and still apply force accurately against an opponent, the safer you will be).

I do not know if it is me to whom you are referring, but I've never said what I think kills, other than to suggest it is large holes and massive damage. I'm not takin' a side pro or con hydrostatic shock, as I believe many factors affect the lethality of a gunshot wound. I'll continue to aim for the center of mass. (That would be about due West of Boston, wouldn't it?)

--Herself

 

[Archangel]

Wikipedia entries on Stopping Power and Hydrostatic Shock.

These should be required reading. Seriously.


I'll just touch on the highlights here:

Hydrostatic shock is a myth. It does not exist.

Physiological incapacitation is caused by damaging the Central Nervous System, either by damaging it directly, or by cutting off its blood supply.

Round nose or pointed FMJ bullets actually leave holes smaller than their outside diameter. FMJ causes significantly less tissue damage per inch of penetration than expanding bullets. Less tissue damage means less bleeding, which means less chance of quickly incapacitating the target if the CNS is not hit directly.


Priorities when selecting a defensive bullet are:
1) Shot placement.
You have to be able to hit where you are aiming, and you should be aiming at the vital areas most likely to cause incapacitation.

2) Adequate penetration.
12.5-14 inches penetration in ballistic gelatin by the IWBA standard, 12-18 by the FBI standard. Less is insufficient. More is acceptable, but is not optimal.

3) Largest amount of tissue damage to the required penetration depth.
A bullet that will expand to the greatest diameter possible while still penetrating to the required 12-18 inch depth causes the most tissue damage, thus the best chance for incapacitation. However, remember #1. .44 magnum gets you nothing if you flinch too bad to hit anything.

 

[Riktoven]

Someone earlier in the thread said that a gun is a tool for transferring force to the target, and thats what kills. I disagree. I think a gun is a tool used to make a hole in the target, the force is just necessary to make the hole, but as long as the hole is made the measure of force is relatively unimportant.

Human tissue isn't water though and most of it compresses unlike water. Most of the ballistics "experts" agree that the permanent crush cavity is the important part of wounding, meaning expansion and penetration. Penetration being the primary wounding implement as it would stop quickest by hitting a vital organ or the central nervous system. Large wound volume from an expanded round be the secondary stopper coming from blood loss over time. Some would pick a fmj round over a jhp if the jhp can't penetrate deep enough in the caliber in question. If a jhp can penetrate deep enough it creates a wound with a larger volume for increased chances of hitting a vital area, and increased area for bleeding.

Some retailers like Extreme Shock! (insert tacticool agent picture here) would have you think that energy dump is the winning ticket. I think this is definately worth reading, it cites several other sources you can read as well. Personally I'll take fackler over blowing up watermelons in the backyard. Ymmv.

Yay, spot on info that won't get people killed.

Hydrostatic shock is real, but I have yet to see a handgun round that could create a large enough pressure wave to DO TISSUE DAMAGE. That pressure wave does exist and it might cause pain as ripples past nerves, but unless that pressure wave significantly disrupts brittle inelastic tissue (say a human liver) it can't be relied upon for wounding. Some high speed pistol rounds can cause such damage if they impact the body right next to such tissue, but by right next to I mean within 1/2 an inch.

Rifles are another matter, and that is where this nonsense about 1 hole going in and nothing comming out being better than two holes comes from. At 3000fps, many rifle rounds will yaw (or better yet yaw, and then fragment) leaving some horrendous tissue wounds, but due to the cross sectional density of a sideways bullet or the tiny mass of the bullet fragments, won't make it out of the body and thus no second hole. Handgun rounds simply aren't capable of that...yet.

Where current handgun rounds are concerned, the pressure wave is simply not enough to do any tissue damage (again except maybe to fragile organs like livers if the pressure wave originates very close to the organ). Force can kill people. Explosions turn people's insides into jelly, often times without so much as exterior bruising, but there is no handheld firearm in existance that generates enough force to mimic those results.

In short, don't use the Force. Use your head and shoot till the threat stops.

 

[Archangel]

Hydrostatic shock is real

True. I am guilty of trying to sum up a little too much.

What I meant was that there in no magical shockwave that travels through the body and damages organs.

While Hydrostatic Shock does exist as a concept, there is no handgun or rifle round capable of creating a shockwave strong enough to damage tissue.

 

[SixForSure]

Just to be technically picky:

Force = mass * acceleration.

Kinetic Energy = mass * velocity^2

Trust me - it's my job.

You are mostly correct, however for Kinetic Energy the gravitational constant of 32.17 also figures in:

Projectile energy in footpounds = (WxVsquared) divided by (64.34x7000)

V= Velocity in feet per second
w= weight in grains (mass)
64.34 is the 2x gravitational constant of 32.17 (you use 32.17 instead of 64.34 if 1/2mass was used in the equation)
the 7000 is to make the answer come out in FtLbs (not grains)


http://www.cruffler.com/BallisticCalculators/BallisticCalculator.shtml

 

[Vern Humphrey]

You are mostly correct, however for Kinetic Energy the gravitational constant of 32.17 also figures in:

Projectile energy in footpounds = (WxVsquared) divided by (64.34x7000)

V= Velocity in feet per second
w= weight in grains (mass)
64.34 is the 2x gravitational constant of 32.17 (you use 32.17 instead of 64.34 if 1/2mass was used in the equation)
the 7000 is to make the answer come out in FtLbs (not grains)


http://www.cruffler.com/BallisticCalculators/BallisticCalculator.shtml

He is correct -- he uses the term "mass" not "weight." Mass = weight / gravitational constant.

So his formula already includes the gravitational constant.

 

[HankB]

for Kinetic Energy the gravitational constant of 32.17 also figures in:

Only if you're trying to get an answer in specific units (ft. lbs) and then, "g" is only factors in indirectly, as it's used in defining a mass unit called the slug according to the formula M = W / g, where M is the mass in slugs, W is the weight in pounds, and g is the acceleration of gravity. (The "7000" in the KE formula corresponds to the number of grains per pound, and the "32.16" is the weight, in pounds, of a slug in a 1g gravitational field.)

 

[SixForSure]

Vern Humphrey and HankB-
Thank you both for explanations that I can understand. I have used and quoted the formula that I posted for years, but had never been able to get an explanation of just how the Gravitational Constant figured in, or for how the definition of mass differs from weight. Thanks again!

 

[bowfin]

Okay, I am no ballistician, or a medical doctor or forensic expert.

I have shot deer, a lot of deer. I can't say how many, but the 50th one was a long, long, time ago. We can now buy permits in Nebraska that are for all intents "unlimited" in number, and I have been invited out to cull deer several times. I have been in on the scene of hunters have shot their deer, and I end up skinning and boning out all my deer, and many for other people. How much of what I see done on a deer carrying over to what a bullet would do to a man is a point for conjecture, but I would definitley put up my observations of a couple hundred deer cut apart against any ballistic medium.

First off, if you definitely want to kill something first time, everytime, quickly, by bleeding it to death, you want an exit wound. Internal bleeding is much slower, because all internal space of a body is already full of organs, muscle, fat, etc. This all put pressure against the source of bleeding. Fat and a full stomach especially can act as a compress, stopping the bleeding. A hole in the body leading to the great outdoors has no counteracting pressure, save air. The exit hole ALWAYS bleeds worse than the entrance wound. I have had many short and long blood trails with a dead deer at the end, and have yet to see the exception.

I also do not buy the theory that if a bullet goes through, is inefficienct because it hasn't "utilized" all of its energy. If it makes a through and through, it has used all it needed, thank you very much. The rest wasn't "wasted", it just wasn't needed. It is difficult to say how much energy is "too much" when it comes to penetration, since less than 90 degree angles of entry/exit, longer ranges, and what the bullet hits before and during the penetration make the job tougher. I would say take the worst case scenario, then get a bullet/load that goes through and through in that instance.

A case could be made of wounding or killing bystanders with overpenetration, but underpenetration could get you killed, plus the people beside and behind you if it means the bad guy doesn't stop shooting because he was "underpenetrated". You are also likely to send fewer bullets downrange if the bad guy was "underpenetrated" on the first shot.

A hit on the spine or brain is the Ace of Spades. I have seen 225+ pound deer go down instantly with a shot that just clips a vertabrae. The spinal cord or backbone doesn't have to be severed at all, or suffer major damage. Even a good whack far back on the tail bone will put an animal down, not always killing them, but leaving plenty of time and opportunity for a coup de grace. I have heard of stunned deer getting up and escaping from hunters, but every story I have heard involves a recovery time that was long enough for a check for life and a finishing shot, and since the deer is gone, no one can say exactly where they were hit.

Breaking various moving parts (bones, ligaments, and major tendons) can also incapacitate rather nicely, but are hard to figure into a plan of action, because, well, they are always moving, to the point that luck is more a factor than skill, Roy Rogers shooting their gun hand excepted.

Hydrostatic shock must be a factor for other than deer, because I haven't seen any other evidence that points to a deer dying from a bullet or arrow, except damage to the nervous system or bleeding to death. Deer must not have "Hydrostats", to get shocked, I guess. I have seen bullets go through diaphragms and just clip the lungs, yet I haven't seen any damage to the lungs, which being a soft, almost fluffy tissue, should be ripped apart by this hydrostatic shock. Denser muscle also seems impervious to hydrostatic shock. I save the livers of all the deer I can, and I haven't seen any permanent damage except that cause by bullet contact. Same goes for the heart, I hover around to claim those from friends or relatives, never seen a ruptured pericardal sac that wasn't holed. I am guessing if I don't see it with a 154 grain 7mm Remington Magnum, the chances of seeing it with a .40 S&W goes way down from zero.

I know people with x-ray high speed cameras see something that can be measured that they call hydrostatic shock, but just because it can be measured doesn't mean it is important. Yes, I have shot cans full of water, and jugs, but the same spectacular damage could be reproduced with hydraulic pressure from a slow moving cylinder.

FMJs (yes, I have seen deer and coyotes killed with them) don't zip through straight, as a rule, They get crossways, swap ends, bend, and wander. They just can't be counted on to do these contortions at the right time in the right place like a well designed expanding bullet. I will say that a longer rifle bullet would be more damaging in this respect, because a long rifle bullet would yaw more than a stubby pistol bullet. Expansion of a bullet is absolutely great, but not at the expense of penetration. I would not trade a double size hole 3/4 of the way through a body for a pencil hole all the way to that desirable exit wound. I don't have to though, I can get a double size mushroomed bullet that goes all the way through 99% of the time, so that is a moot point. It may not be for handguns, though, but if you can't have expansion and an exit wound both, take the exit wound, and make it with a bigger caliber bullet.

I can't say I have taken every factor into account or might not drawn the wrong conclusions from the results, but from the time I have formed these opinions, every shot afterwards has supported them rather than contradicted them. I am always open to a having an epiphany on these beliefs with the next shot or your next post, though.

 

[HankB]

The ideal bullet would completely penetrate a target, and upon exiting, fall to the ground, spent.

This isn't going to happen except as an incredibly rare fluke, as the (hopefully) expanded bullet, being rather blunt, is either going to stop in the skin on the off-side of the game, or penetrate completely and keep going.

As far as hydrostatic shock, I think it's rare, but possible, at least with rifle ammo. I remember vividly one zebra I shot with a .30/06. The animal was quartering towards me, and he dropped straight down when hit. I mean, he didn't take one step or go over on his side, he went straight down on his belly as if someone had dropped a Buick on his back. As I approached he s-l-o-w-l-y rolled over on one side, and a stream of blood exactly like the stream from a drinking fountain came out of his neck.

I didn't hit bone or CNS, but the bullet hit squarely on what I suppose is the carotid artery, with shock traveling both up to his brain and down to his heart - he didn't so much as twitch. That's the one instance when hunting I've seen where hydrostatic shock seemed to be present.

 

[clone]

do flat point or wad cutters create a wider wound channel?

 

[Riktoven]

do flat point or wad cutters create a wider wound channel?

heh...they do in paper. I've never seen anything living shot with one, but I imagine the wound channel or permanent stretch cavity (whatever terminology floats your boat) would be wider at the cost of penetration.

 

[Vern Humphrey]

heh...they do in paper. I've never seen anything living shot with one, but I imagine the wound channel or permanent stretch cavity (whatever terminology floats your boat) would be wider at the cost of penetration.

Vernal Smith addressed that question in respect to semi-wadcutters. He mixed sand with ballistic geletin and fired bullets dipped with paint into it. Semi-wadcutters had paint on the noses, but not on the shoulders, indicating the shoulder "flew in a vacuum" as he put it.

I suspect flatpoints would be better than round-noses, and a flat point is an ideal penetrator. Full wadcutters would cut a full channel.

 

[RyanM]

Wikipedia entries on Stopping Power and Hydrostatic Shock.

These should be required reading. Seriously.

I can't resist such an opportunity to toot my own horn. I started both of those articles, as well as the Energy Transfer article. Other members of Wikipedia fleshed them out and improved the readability, but I started 'em, and most of the information from the first versions has survived intact (unlike the majority of Wikipedia articles).