Wounding mechanisms

[Skribs]

Back when I first got into guns, I had a very limited understanding of wound channels. My basic premise was: if a bullet is going under 2000 FPS, the wound tract is roughly the size and shape of the bullet. If a bullet is going over 2000 FPS, the wound tract gets proportionally bigger.

Over the past month or so, I've been doing as much second-hand research as I can (i.e. not shooting gel blocks myself, but looking at what others have done). A lot has been done, and publicly posted, in the last several years. The ability to see many different tests done in slow motion instead of in a final still image has led to a much different understanding. However, I don't have simple numbers anymore, as I believe the equations have gotten much more complex.

From what I can tell, there are three primary wounding mechanisms:

1. Crush damage
2. Cavitation damage
3. Fragmentation damage

Crush damage is basically what I had thought of before, although with some caveats. At the very least, a bullet will poke a hole through the target. The size of the hole depends on the size and shape of the bullet. A bigger bullet will leave a bigger hole. A flatter nose will leave a bigger hole.

Crush damage can be increased by expansion, fragmentation, or tumbling; at a loss of penetration.

Cavitation is the effect that a bullet's velocity, weight, diameter, and shape have on the transfer of energy through the target. A light, slow, small, round-nosed bullet will have a very low cavitation. A large, heavy, fast, blunt bullet will have a high degree of cavitation. This is why a shotgun slug, even moving at less than 2000 FPS, will have a massive cavity. As to shape, this is where something like a fluted bullet comes into play.

The process of deformation or destabilization (i.e. tumbling) can also lead to cavitation damage. This tends to create a wider bulge in the wound tract, but not necessarily a wider overall wound tract than the more permanent properties of a bullet.

Fragmentation can happen on impact (i.e. Glazer Safety Slug), during terminal ballistics (i.e. a 55-grain 5.56mm FMJ), or even before the round is loaded from the factory (i.e. a shotshell). What fragmentation does is amplify the effects of the other two wounding mechanisms, but often for a very shallow distance. Fragmentation increases crush damage by increasing the surface area of the round. Fragmentation increases cavitation damage by helping to tear elastic tissue that would otherwise have snapped back into place.

At least, this is my current understanding of how bullets (or pellets) affect the target. It's helping me build my new plans for what types of ammo to load for self-defense. (Put simply, buckshot in shotguns, FMJs in AR-type rifles, and fluted bullets in handguns).

Did I miss something? Get something wrong? Are there better numbers for the above?

 

[Thomasss]

I think you still have a lot to learn. A 55 grain 5.56 travelling at 3000fps will cause a lot of Cavitation. Many high speed bullets will produce a shockwave in the body near the wound channel without ever coming in direct contact with the projectile. "Just wing 'em." or go for a shoulder shot or shoot him in the leg just to slow him down." old cowboy TV dialog. Any of those scenarios can be lethal. In self defense, the purpose is to stop the threat. I don't suppose you have ever seen what a muzzle loader or bird shot in a shotgun load can do. They are way under 2000 fps. How about a LSWC .38 Special with a nominal velocity of 800 fps. Point of impact, velocity, bullet expansion have been around for a long time, but they are more efficient than they used to be. Fragmentation really increases Crush damage more. FMJs are incorrect for ARs. FMJ can travel farther than one might think and do a thru and thru in both bodies and walls. Always consider what is beyond your target and choose your ammo wisely.

 

[tark]

I think you still have a lot to learn.

Ok, so specifically tell us what it is he needs to learn. Seems to me Skribs nailed it pretty well.

 

[Skribs]

I think you still have a lot to learn. A 55 grain 5.56 travelling at 3000fps will cause a lot of Cavitation. Many high speed bullets will produce a shockwave in the body near the wound channel without ever coming in direct contact with the projectile. "Just wing 'em." or go for a shoulder shot or shoot him in the leg just to slow him down." old cowboy TV dialog. Any of those scenarios can be lethal. In self defense, the purpose is to stop the threat. I don't suppose you have ever seen what a muzzle loader or bird shot in a shotgun load can do. They are way under 2000 fps. How about a LSWC .38 Special with a nominal velocity of 800 fps. Point of impact, velocity, bullet expansion have been around for a long time, but they are more efficient than they used to be. Fragmentation really increases Crush damage more. FMJs are incorrect for ARs. FMJ can travel farther than one might think and do a thru and thru in both bodies and walls. Always consider what is beyond your target and choose your ammo wisely.

Did you read more than the first paragraph of my post?

 

[45/30-06OKIE]

Back when I first got into guns, I had a very limited understanding of wound channels. My basic premise was: if a bullet is going under 2000 FPS, the wound tract is roughly the size and shape of the bullet. If a bullet is going over 2000 FPS, the wound tract gets proportionally bigger.

Over the past month or so, I've been doing as much second-hand research as I can (i.e. not shooting gel blocks myself, but looking at what others have done). A lot has been done, and publicly posted, in the last several years. The ability to see many different tests done in slow motion instead of in a final still image has led to a much different understanding. However, I don't have simple numbers anymore, as I believe the equations have gotten much more complex.

From what I can tell, there are three primary wounding mechanisms:

1. Crush damage
2. Cavitation damage
3. Fragmentation damage

Crush damage is basically what I had thought of before, although with some caveats. At the very least, a bullet will poke a hole through the target. The size of the hole depends on the size and shape of the bullet. A bigger bullet will leave a bigger hole. A flatter nose will leave a bigger hole.

Crush damage can be increased by expansion, fragmentation, or tumbling; at a loss of penetration.

Cavitation is the effect that a bullet's velocity, weight, diameter, and shape have on the transfer of energy through the target. A light, slow, small, round-nosed bullet will have a very low cavitation. A large, heavy, fast, blunt bullet will have a high degree of cavitation. This is why a shotgun slug, even moving at less than 2000 FPS, will have a massive cavity. As to shape, this is where something like a fluted bullet comes into play.

The process of deformation or destabilization (i.e. tumbling) can also lead to cavitation damage. This tends to create a wider bulge in the wound tract, but not necessarily a wider overall wound tract than the more permanent properties of a bullet.

Fragmentation can happen on impact (i.e. Glazer Safety Slug), during terminal ballistics (i.e. a 55-grain 5.56mm FMJ), or even before the round is loaded from the factory (i.e. a shotshell). What fragmentation does is amplify the effects of the other two wounding mechanisms, but often for a very shallow distance. Fragmentation increases crush damage by increasing the surface area of the round. Fragmentation increases cavitation damage by helping to tear elastic tissue that would otherwise have snapped back into place.

At least, this is my current understanding of how bullets (or pellets) affect the target. It's helping me build my new plans for what types of ammo to load for self-defense. (Put simply, buckshot in shotguns, FMJs in AR-type rifles, and fluted bullets in handguns).

Did I miss something? Get something wrong? Are there better numbers for the above?

Ok so for most bad guys, any reasonable caliber will take them out, are you wanting to know the physics behind wounds and such? If so this may not be the most correct place to learn that, unless we have some resident EMT or surgeon types on here?

 

[Balrog]

Back when I first got into guns, I had a very limited understanding of wound channels. My basic premise was: if a bullet is going under 2000 FPS, the wound tract is roughly the size and shape of the bullet. If a bullet is going over 2000 FPS, the wound tract gets proportionally bigger.

Over the past month or so, I've been doing as much second-hand research as I can (i.e. not shooting gel blocks myself, but looking at what others have done). A lot has been done, and publicly posted, in the last several years. The ability to see many different tests done in slow motion instead of in a final still image has led to a much different understanding. However, I don't have simple numbers anymore, as I believe the equations have gotten much more complex.

From what I can tell, there are three primary wounding mechanisms:

1. Crush damage
2. Cavitation damage
3. Fragmentation damage

Crush damage is basically what I had thought of before, although with some caveats. At the very least, a bullet will poke a hole through the target. The size of the hole depends on the size and shape of the bullet. A bigger bullet will leave a bigger hole. A flatter nose will leave a bigger hole.

Crush damage can be increased by expansion, fragmentation, or tumbling; at a loss of penetration.

Cavitation is the effect that a bullet's velocity, weight, diameter, and shape have on the transfer of energy through the target. A light, slow, small, round-nosed bullet will have a very low cavitation. A large, heavy, fast, blunt bullet will have a high degree of cavitation. This is why a shotgun slug, even moving at less than 2000 FPS, will have a massive cavity. As to shape, this is where something like a fluted bullet comes into play.

The process of deformation or destabilization (i.e. tumbling) can also lead to cavitation damage. This tends to create a wider bulge in the wound tract, but not necessarily a wider overall wound tract than the more permanent properties of a bullet.

Fragmentation can happen on impact (i.e. Glazer Safety Slug), during terminal ballistics (i.e. a 55-grain 5.56mm FMJ), or even before the round is loaded from the factory (i.e. a shotshell). What fragmentation does is amplify the effects of the other two wounding mechanisms, but often for a very shallow distance. Fragmentation increases crush damage by increasing the surface area of the round. Fragmentation increases cavitation damage by helping to tear elastic tissue that would otherwise have snapped back into place.

At least, this is my current understanding of how bullets (or pellets) affect the target. It's helping me build my new plans for what types of ammo to load for self-defense. (Put simply, buckshot in shotguns, FMJs in AR-type rifles, and fluted bullets in handguns).

Did I miss something? Get something wrong? Are there better numbers for the above?

I think your summary of wound mechanics is good but secondary to shot placement and penetration.

 

[Skribs]

Ok so for most bad guys, any reasonable caliber will take them out, are you wanting to know the physics behind wounds and such? If so this may not be the most correct place to learn that, unless we have some resident EMT or surgeon types on here?

It's entirely probable that on a gun forum, we have people with more knowledge than me about how bullets work.

 

[CDW4ME]

Larger holes have better incapacitation potential, given same shot placement.
Which is why expansion is desirable and of course the bullet needs sufficient penetration, it may have to penetrate a forearm.
The criteria of at least 12'' penetration with consistent expansion addresses both.

What if the bullet one is carrying doesn't meet at least 12'' penetration with consistent expansion?
Then ya say, "Its all about shot placement"
Uh yea, we know. That doesn't improve the performance of whatever deficient bullet is the subject of discussion.
Alternate performance criteria invoked: Well... "I wouldn't want to or nobody volunteer to, get shot with it". <--- End all of wounding mechanisms that is.

 

[trackskippy]

I think one important thing that was missed here is "volume". If one of your magic bullets works great, rapid applications of multiples of that can only be better.

Shoot first, shoot fast, and shoot often. Dont be stingy with your precious metals.

 

[45/30-06OKIE]

It's entirely probable that on a gun forum, we have people with more knowledge than me about how bullets work.

Yeah, I'm not trying to belittle your post, although it may seem like it cause text never sounds the same in your head as it does mine lol! It's an interesting topic.

 

[21H40]

It's entirely probable that on a gun forum, we have people with more knowledge than me about how bullets work.

Unfortunately there aren't enough science based studies to answer these questions without a doubt. On the gun forum you get lots of opinions, sometimes influenced by "studies" (I haven't seen anything quoted that meet peer review levels of authenticity), hunting experience, and various forms of urban legend.

Some of us have seen firearms used on actual people, but, again, those aren't statistically relevant. General conclusions are fair - for instance IME humans can be surprisingly resilient when shot, even when on the receiving end of a 30mm burst. Sometimes they are not, and a little piece of shrapnel is terminal despite the fact that 99% of the body is healthy.

I don't think trauma surgeons care about the same factors that we are looking for - I expect most of them classify wounds into three categories:
1. Repair/remove tissue and bone
2. Seal and stop blood loss
3. Good enough to leave it alone

We're playing a game of averages with more variables than most of us could ever count. Some people are fine always betting on the horse with the least chance to win - but the biggest pay-off if it happens. I'm more of a 'stack the deck' kind of gambler - I want to control every variable I can and compensate for the rest with whatever advantages I can find.

 

[Thomasss]

Did you read more than the first paragraph of my post?

If you read my entire paragraph, you will see that I read your entire thread. You have learned a lot, but there is much more to understand. I meant no disrespect, however, as you stated "Did I miss something?"
Yes, you did and I explained what you missed.

 

[J-Bar]

Based on the above comments there must be at least one more type of wound than the 3 identified in the original post. Call it "surgical" until a better adjective is found. Consider the wound made by an arrow. Even if the broadhead doesn't cut a major bleeder, damage to the lungs can cause pneumothorax which can be fatal. No crushing, cavitation, or fragmentation involved. OK. this is a firearms forum, so consider a low velocity hard ball from a muzzle loader or snubbie revolver. Even without crushing tissues, cavitation, fragmentation, or hemorrhage, lung damage or central nervous system damage from non-expanding projectiles can fatal as well as incapacitating. I've seen it many times over 22 years as a veterinarian.

 

[tark]

It's entirely probable that on a gun forum, we have people with more knowledge than me about how bullets work.

That is quite an understatement There are usually people on any large forum that have forgotten more about a given subject than the rest of us will ever know. ( I am not one of them )

 

[bubbatime]

And remember , surgeons have limited data in which to inform their opinions. Tons of people shot with bullets die before they even make it to a surgeon. Maybe a medical examiner in a large area like Chicago would have better data.

 

[entropy]

Terminal ballistics is a science unto itself, and research can only be done in a few ways, almost all of them after the fact. There are many factors that are not related to the projectile at all that will determine effect on target.
Living beings are not made of ballistic gelatin, there are bones in there, and they can play hell with ballistics and effect.
Adrenaline can have quite an effect on a live target, to include nullifying it for a period of time, though eventually that wears off.
Mental predisposition of how to react to a gunshot wound can have effect also. Many people have died from gunshots others would have not only survived, but could have continued whatever actions that caused them to be shot in the first place.
I understand what Thomasss was trying to say, but I'd say Skribs has a good foundation on the subject.

 

[dweis]

Dr. Vincent DiMaio is a renounce forensic pathologist. He is the author of Gunshot Wounds, a 401 page book that is considered a bible in the forensics field. His knowledge was developed through performing or witnessing thousands of autopsies of gunshot victims. The book can be borrowed from the Internet Library at this URL:
https://archive.org/details/Gunshot...ts_Of_Firearms_Ballistics_Forensic_Techniques

The paragraphs below are from the book. It shows the depth of the writing, and the entire book is just as analytical. If you want to understand wound ballistics, read the book.

As a bullet moves through the body, it crushes and shreds the tissue in its path, while at the same time flinging outward (radially) the surrounding tissue from the path of the bullet, producing a temporary cavity considerably larger than the diameter of the bullet.1,2 This temporary cavity, which has a lifetime of 5 to 10 msec from initial rapid growth until collapse, undergoes a series of gradually smaller pulsations and contractions before it finally disappears, leaving the permanent wound track (Figure 3.1). It is the combination of the crushed and shredded tissue and the effects of the temporary cavity on tissue adjacent to the bullet path (shearing, compression, and stretching) that deter- mines the final extent of a wound.

The location, size, and the shape of the temporary cavity in a body depend on the amount of kinetic energy lost by the bullet in its path through the tissue, how rapidly the energy is lost, and the elasticity and cohesiveness of the tissue. The maximum volume and diameter of this cavity are many times the volume and diameter of the bullet. Maximum expansion of the cavity does not occur until some time after the bullet has passed through the target. The temporary cavity phenomenon is significant because it has the potential of being one of the most important factors in determining the extent of wounding in an individual. For this potential to be realized, however, not only must a large temporary cavity be created but it must develop in strategically important tissue, e.g., a cavity in the liver is more significant than one located in the thigh.

In the case of handgun bullets, the bullet produces a direct path of destruction with very little lateral extension within the surrounding tissues, i.e., only a small temporary cavity is produced. As a general rule, the temporary cavity plays little or no role in the extent of wounding. To cause significant injuries to a structure, a handgun bullet must strike that structure directly. The amount of kinetic energy lost in the tissue by the bullet is insufficient to cause the remote injuries produced by a high-velocity rifle bullet.

If a 9-mm hollow-point bullet expands (mushrooms) to 12 mm in pass- ing through an organ, the amount of tissue crushed and shredded will, theoretically, be greater than if the bullet did not expand or if it was a solid bullet. In reality, a solid or non-expanding bullet may produce equal if not more direct injury to tissue, if it tumbles after achieving penetration while the hollow-point doesn’t. Solid bullets may even be more lethal than mush- rooming bullets. As a general rule, mushrooming bullets do not penetrate as deeply as solid bullets because they mushroom. If the aorta, for example, is 14 inches from the skin surface and the mushrooming bullet stops after 12 inches of penetration but the solid bullet travels for 18 inches, then the solid bullet is more lethal than the hollow-point.

 

[Skribs]

The criteria of at least 12'' penetration with consistent expansion addresses both.

What if the bullet one is carrying doesn't meet at least 12'' penetration with consistent expansion?

Some bullets do quite well without expanding, using other means to achieve similar results.

Some bullets come in calibers where expansion is not a preference.

I think one important thing that was missed here is "volume". If one of your magic bullets works great, rapid applications of multiples of that can only be better.

Yes, excellent point.

Especially with rounds of medium reliability. Say a hollowpoint that sometimes expands, or a 5.56mm round that might tumble right away, or might tumble several inches into the target. If you fire one round, that unpredictability can be a problem. If you fire several rounds, that unpredictability may give you coverage that is situationally beneficial.

Unfortunately there aren't enough science based studies to answer these questions without a doubt. On the gun forum you get lots of opinions, sometimes influenced by "studies" (I haven't seen anything quoted that meet peer review levels of authenticity), hunting experience, and various forms of urban legend.

Very true. I hope I'm getting better and better at seeing through what is urban legend and what is verifiable. However, I would argue that hunting experience is at least moderately relevant.

Yes, you did and I explained what you missed.

Half of what you said are things that I did mention in my thread as things I've learned (i.e. fragmentation increasing the effects of the others). The other half were things that are out-of-scope of this thread (i.e. shot placement; whenthe discussion mechanism is on wounding mechanisms, which implies shot has been placed).

I had to read your post to know that you had not read mine.

Based on the above comments there must be at least one more type of wound than the 3 identified in the original post. Call it "surgical" until a better adjective is found. Consider the wound made by an arrow. Even if the broadhead doesn't cut a major bleeder, damage to the lungs can cause pneumothorax which can be fatal. No crushing, cavitation, or fragmentation involved. OK. this is a firearms forum, so consider a low velocity hard ball from a muzzle loader or snubbie revolver. Even without crushing tissues, cavitation, fragmentation, or hemorrhage, lung damage or central nervous system damage from non-expanding projectiles can fatal as well as incapacitating. I've seen it many times over 22 years as a veterinarian.

Delayed effects?

How long does a pnu...pnumo...how long does this wound take to have an effect on an assailant?

Other similar effects include infection (especially from something like say point-blank birdshot with fabric and burnt powder in the wound). While I guess it does relate to the OP as written, it doesn't relate to my intent in the OP, which was how to most reliably stop an attack.

That is quite an understatement There are usually people on any large forum that have forgotten more about a given subject than the rest of us will ever know. ( I am not one of them )

While true, a lot of that knowledge may have been urban legend!

 

[upptick]

And remember , surgeons have limited data in which to inform their opinions. Tons of people shot with bullets die before they even make it to a surgeon. Maybe a medical examiner in a large area like Chicago would have better data.

At one point the Army was sending their trauma surgeons to New Orleans Charity Hospital precisely because of the exponentially greater damage caused by AK and AR rounds compared to handgun calibers and New Orleans criminals apparently favor rifles which meant there was a big opportunity for the surgeons to practice....

 

[AlexanderA]

"Terminal ballistics" is a subject that doesn't interest me. In fact I'm rather squeamish about it. Suffice it to say that guns are "adequately destructive."

 

[J-Bar]

How long does a pnu...pnumo...how long does this wound take to have an effect on an assailant?

Pneumothorax means there is air between the outside of the lung and the body wall. If caused by a projectile then it's a "sucking chest wound" which collapses the lungs and is considered immediately life threatening because how long can you hold your breath? I suspect those deer that run 100 yards die as much from pneumothorax as anything else.

 

[230RN]

Skribs did a pretty good analysis of the basic wounding mechanisms in a general, or basically standardized "target material" without considering unpredictable things like bones and which organs would be damaged.

Good thinking in that respect. I'm reasonably sure each item has been covered before, one way or another, but this is a good compendium of the basics in one place and worth reviewing here in THR.

One item I discussed once was the damaging and impact effect of the muzzle blast at different ranges, including contact shots, but that's apart from the direct "missile damage."

And I was always amazed at the description of the damage to Lee Harvey Oswald with a lowly .38 snubby. Sounds like that bullet had a pre-planned route for maximum damage.

And let's face it: placement. You could probably stop a charging elephant with a .22 short to the eyeball. Not that I want to test this, you understand.

"No elephants were harmed in the testing of this ammunition."

Nice analysis, Skribs ! =D

Terry, 230RN

REF (Icky-poo, yuchful wounds of LHO):
https://www.upi.com/Archives/1963/1...lly-injured-by-time-he-arrived/8181204553842/

Optional: Search term <bullet testing on pigs>.

 

[481]

Back when I first got into guns, I had a very limited understanding of wound channels. My basic premise was: if a bullet is going under 2000 FPS, the wound tract is roughly the size and shape of the bullet. If a bullet is going over 2000 FPS, the wound tract gets proportionally bigger.

Over the past month or so, I've been doing as much second-hand research as I can (i.e. not shooting gel blocks myself, but looking at what others have done). A lot has been done, and publicly posted, in the last several years. The ability to see many different tests done in slow motion instead of in a final still image has led to a much different understanding. However, I don't have simple numbers anymore, as I believe the equations have gotten much more complex.

From what I can tell, there are three primary wounding mechanisms:

1. Crush damage
2. Cavitation damage
3. Fragmentation damage

Crush damage is basically what I had thought of before, although with some caveats. At the very least, a bullet will poke a hole through the target. The size of the hole depends on the size and shape of the bullet. A bigger bullet will leave a bigger hole. A flatter nose will leave a bigger hole.

Crush damage can be increased by expansion, fragmentation, or tumbling; at a loss of penetration.

Cavitation is the effect that a bullet's velocity, weight, diameter, and shape have on the transfer of energy through the target. A light, slow, small, round-nosed bullet will have a very low cavitation. A large, heavy, fast, blunt bullet will have a high degree of cavitation. This is why a shotgun slug, even moving at less than 2000 FPS, will have a massive cavity. As to shape, this is where something like a fluted bullet comes into play.

The process of deformation or destabilization (i.e. tumbling) can also lead to cavitation damage. This tends to create a wider bulge in the wound tract, but not necessarily a wider overall wound tract than the more permanent properties of a bullet.

Fragmentation can happen on impact (i.e. Glazer Safety Slug), during terminal ballistics (i.e. a 55-grain 5.56mm FMJ), or even before the round is loaded from the factory (i.e. a shotshell). What fragmentation does is amplify the effects of the other two wounding mechanisms, but often for a very shallow distance. Fragmentation increases crush damage by increasing the surface area of the round. Fragmentation increases cavitation damage by helping to tear elastic tissue that would otherwise have snapped back into place.

At least, this is my current understanding of how bullets (or pellets) affect the target. It's helping me build my new plans for what types of ammo to load for self-defense. (Put simply, buckshot in shotguns, FMJs in AR-type rifles, and fluted bullets in handguns).

Did I miss something? Get something wrong? Are there better numbers for the above?

I don't believe that you are missing much in the general sense that you are approaching the topic.

Although it's a somewhat nuanced point, crush damage, which results from direct contact with the projectile, encompasses damage done both by the projectile itself and any fragmentation (which is, or least was, part of the projectile) so describing it as another wounding mechanism separate from ''crush damage'' is probably not entirely correct since the wounding produced by fragmentation is also the result of direct contact with the projectile's fragments.

I would suggest that wounding mechanisms (whether they arise from permanent or temporary cavity formation) are more accurately classified by their physiological effects which would reduce the number of mechanisms to one:

1. Tissue damage (which is a product of the stress (force) that occurs radially along—and adjacent to—the bullet's path during both permanent and temporary cavity formation)

Even though hypovolemia (which is a product of both hard and soft tissue damage) might also be considered by some to be a wounding mechanism itself, because blood loss arises from tissue damage, hypovolemia resulting from blood loss is probably more correctly regarded as an effect of the tissue damage wounding mechanism than an independent wounding mechanism itself.

 

[Skribs]

"Terminal ballistics" is a subject that doesn't interest me. In fact I'm rather squeamish about it. Suffice it to say that guns are "adequately destructive."

In much the same way as I prefer to buy a cheeseburger than to hunt.

Skribs did a pretty good analysis of the basic wounding mechanisms in a general, or basically standardized "target material" without considering unpredictable things like bones and which organs would be damaged.

True. For the most part, that's the next layer of the onion.

Except that some effects of bone can be included here, such as the effect bone has on the projectile, or effects bone has on becoming part of the projectile.

One item I discussed once was the damaging and impact effect of the muzzle blast at different ranges, including contact shots, but that's apart from the direct "missile damage."

Another interesting topic, it's a shame I missed it. But also yes, slightly out of scope of this thread.

And I was always amazed at the description of the damage to Lee Harvey Oswald with a lowly .38 snubby. Sounds like that bullet had a pre-planned route for maximum damage.

Bullets zig-zagging does increase the potential volume of the wound channel, but is also probably one of the least predictable wounding methods. Unless you have bullets that can be controlled like Yondu's arrow from Guardians of the Galaxy.

And let's face it: placement. You could probably stop a charging elephant with a .22 short to the eyeball. Not that I want to test this, you understand.

One of the most difficult aspects of terminal ballistic study is the ethics of live testing.

This is also why I think hunting experiences are as relevant as the scientific tests that people do.

Although it's a somewhat nuanced point, crush damage, which results from direct contact with the projectile, encompasses damage done both by the projectile itself and any fragmentation (which is, or least was, part of the projectile) so describing it as another wounding mechanism separate from ''crush damage'' is probably not entirely correct since the wounding produced by fragmentation is also the result of direct contact with the projectile's fragments.

1. Tissue damage (which is a product of the stress (force) that occurs radially along—and adjacent to—the bullet's path during both permanent and temporary cavity formation)

IMO, "tissue damage" is another way of describing the topic of "wounding mechanisms", and what I'm describing are different ways in which tissue can be damaged.

I'm going to oversimplify it here, but if tissue (or a tissue analog) gets hit by a moderately powerful round, there is a temporary cavity created around said round, which will snap back once the energy transfer is complete. However, if there are fragments included, then the tissue will be torn. The two effects of cavitation and fragmentation cause additional damage than one or the other would have caused by themselves. This is why I included them as separate.

The fragmentation can cause damage through each individual pellet or fragment, yes. But when combined with a stretch cavity, it's a powerful combo.

 

[wayneinFL]

"Terminal ballistics" is a subject that doesn't interest me. In fact I'm rather squeamish about it. Suffice it to say that guns are "adequately destructive."

Terminal ballistics are the end result, the only result that matters. The same goes if you're punching holes in paper with a wadcutter, pinging steel, killing a rat, harvesting a deer, or stopping an attack.