💀 Quarry: What kills’em dead – the Mechanics of Killing

[JungleShooter]

Quarry: What kills’em dead – the Mechanics of Killing 



This thread is PART (1) of a four-part series (cf. below for links to the other threads).



What kills is a Permanent HOLE in the quarry – nothing else

We use projectiles (pellets and slugs) to kill quarry. But what exactly kills a shot animal (apart from septicemia)?
We say we want to “dump energy” and getting more “energy transfer” – and we know of course that it’s not the energy in and of itself that destroys and kills – we can fire a bullet into a bucket of water and the water absorbs all of the bullet’s energy – but nothing gets destroyed!

So, it’s not more “energy” that we want inside of the animal: It’s more destructive work done by the energy inside of the animal!



• The destructive work of a projectile is slicing and crushing (destroying!) the quarry’s tissue (penetrating trauma). The crushed tissue causes a permanent hole, the permanent wound cavity. And scientifically, medically, what kills is a permanent HOLE in the quarry – nothing else. (cf. sources below*)



• There is also non-destructive work done by some of the energy: The momentary stretching of the neighboring tissue along the permanent HOLE, resulting in a temporary wound cavity. At airgun velocities this temporary wound cavity normally does NOT cause any damage. However, in non-elastic “clay quarry” and “play-dough animals” the temporary wound cavity looks permanent and very impressive (esp. to potential subscribers). But clay and play-dough are non-elastic and thus greatly exaggerate the effects of a projectile – the quarry’s tissue is elastic and the only real damage is the permanent HOLE.
And to at least mention the “hydrostatic shock,” even disputed among high velocity ballisticians: We simply admit that the “hydrostatic shock” is not a factor at the low velocities of our AG.







For the HOLE to kill – it must be in the right place in the quarry

There are two main ways of how the crushed tissue of the permanent wound cavity leads to death (aside from septicemia/ infections, or starvation due to a destroyed jaw):

(1) The function of body parts immediately necessary for survival is hindered, i.e.:
• Brain and spine (central nervous system CNS) are needed not only for voluntary coordinated use of extremities but also for the involuntary control of essential internal body parts (heart!), i.e., “living”.

• Heart, lungs, and the major arteries/veins are needed to transport oxygen to the brain which is essential for its functioning.



(2) The crushed tissue of various organs and muscle tissue includes arteries/veins that are now open and are bleeding (hemorrhaging). The more blood is lost, the less oxygen arrives at the brain which it needs for its functioning (“living”!). And if the blood is lost rapidly, the quarry can be incapacitated due to the quick decrease in blood pressure.



A HOLE is only deadly if it is in the right place. Therefore, shot placement is first!







The projectiles that make a Better HOLE in the quarry are –– larger, faster, bulldozer-nose, expanding projectiles

After addressing shot placement(!), we can try to improve the permanent wound cavity as follows:

(1) The wider the diameter of the projectile (pellet or slug) the wider the diameter of the HOLE. And more crushed tissue is better.
➔ Therefore, a larger caliber can be an advantage. Or a projectile that expands upon impact – that’s where the hollow points come in.



(2) The deeper the projectile penetrates the quarry the longer the HOLE. And again, more crushed tissue is better than less.

And:
(3) A HOLE with two blood drains (entrance and exit wound) bleeds better than a hole with only one drain. More blood loss in less time kills quicker.
➔ Therefore, with all other things equal, a higher velocity is better. (Typical AG quarry are so small that too little penetration is rarely a problem.)



(4) The larger the meplat – the flat surface of the projectile – the more tissue will actually be crushed when making the HOLE.
(4a) ➔ Therefore:
• Flat points or wadcutters with their very large meplat and sharp edge crush the most tissue (80-90%+ of the projectile’s diameter).

• Second are unexpanded hollow points, with some having meplats as large as wadcutters, though some others have much smaller meplats (the hollow point cup is part of the meplat). 

• Last are domed and pointed projectiles that crush only 65-70% of the tissue [figures adapted from Schaefer, 2014-2018, from PB]. Domed and pointed projectiles have a tendency to push the tissue aside instead of crushing it. They cut through flesh much like a welldriller – with ease the drill goes in deep. Clearly, a bulldozer-nose is better than a welldriller-nose. Domed pellets have a higher BC when passing through air, and have therefore also a higher “tissue BC” (as Bob Sterne [GTA: rsterne] describes this).



(4b) ➔ Additionally, hollow points that expand their overall diameter upon impact will crush more tissue (usually, they also expand their meplat). For example, a .22 cal projectile that expands to .295 increases its impact area by 85%, resulting in 85% more tissue crushed! (in metric measurements: A 5.5mm projectile that expands by only 2mm to 7.5mm causes 85% more crushed tissue.)
Note that for a substantial HP expansion the impact velocity must be fairly high, usually at least 700 to 800fps.



(4c) ➔ Sometimes a hollow point projectile will not expand beyond its original diameter. Nevertheless, often its hollow point cup does expand – thus enlarging the meplat. This results in more tissue being crushed.
In many cases hollow points fly with a much better BC than either a wadcutter or a pellet with a larger caliber (and with the same weight) – but upon impact they expand and crush as much tissue as the wadcutter or as the larger caliber pellet: that is the best of both worlds...!



(5) Some projectiles fragment inside the quarry. The HP pellets with ballistic tip usually shed the tip, some pellets leave their expanded head behind and only base with the skirt continues forward (e.g., RWS Super-H-Point), and some projectiles simply come to pieces at very high impact velocities. Sometimes these fragments could create their own wound cavities and increase tissue damage, though at the low AG velocities this is less likely.



(6) Exception for the above principles of a better HOLE:
For some quarry and certain shots we need to make the HOLE into a tough skull before the projectile can do damage to the brain.
➔ Therefore, to break through hard bone the best projectile will have a high impact velocity to actually break through (= the threshold velocity). It will be made from harder lead (lead with a high antimony content, e.g. H&N pellets). It will be domed or pointed rather than a projectile with a large meplat (the flat area that wadcutters and many hollow point pellets have). And it will have a higher sectional density (i.e., heavier if the diameter [caliber] remains the same, or – if the caliber can be varied, rather thin and long, than thick and short).







This thread is PART (1) of a four-part series, here in logical order and with links to each:



● PART (1) Quarry: What kills’em dead – the Mechanics of Killing
[The current thread.]



● PART (2) How Much Hollow Point Expansion Does How Much More Damage?
• A larger projectile makes a larger HOLE.
• So, how much larger is the HOLE if I go from .177 cal to .25 cal? (results in Table 1)
• And how much larger is the HOLE if my hollow point projectile expands 1/10 of an inch? Or 1mm? (results in Table 2)

https://www.airgunnation.com/topic/%f0%9f%94%b4-how-much-hollow-point-expansion-does-how-much-more-damage/



● PART (3) Hollow Point Pellets – Comparison of Specs & Performance
The attached HP Pellet Specs & Performance Chart (.22cal) answers some of the following questions:
• Which HP projectiles expand better to make a Better HOLE in the quarry? –– The faster, softer HP projectiles with larger, deeper HP cups, and expansion aids do!
• What HP pellets are out there? And how do they compare (specs!)?
• How far could I shoot a certain HP pellet and still expect expansion (given the power of my gun)?
• Some HP are really long and might not fit into my magazine…: How long are the long ones really?

https://www.airgunnation.com/topic/%f0%9f%94%b4-hollow-point-pellets-comparison-of-specs-performance/



● PART (4) Hollow Points – Testing How Much They Expand and How Far They Penetrate
Every hollow point projectile (pellet or slug) performs differently, in line with its specs and the conditions. Find a collection of Projectile Expansion and Penetration Test results for both HP pellets and slugs.
(4a) HP Pellet Projectile Expansion and Penetration Tests

https://www.airgunnation.com/topic/%f0%9f%94%b4hollow-point-pellets-testing-how-much-they-expand-and-how-far-they-penetrate/

(4b) HP Slug Projectile Expansion and Penetration Tests

https://www.airgunnation.com/topic/%f0%9f%94%b4-slugs-testing-how-much-they-expand-and-how-far-they-penetrate/#post-749008



I hope this will be helpful to some! 

Matthias





*Sources:
Matt. (2019). Terminal ballistics: How bullets wound and kill. Retrieved from the Everyday Marksman website, at
https://www.everydaymarksman.co/marksmanship/terminal-ballistics/

Fackler, Martin L. (1988). Effects of small arms on the human body. Research Report. Letterman Army Institute of Research, Division of Military Trauma Research. Retrieved from
https://web.archive.org/web/20120218212956/http://ammo.ar15.com/project/Fackler_Articles/effects_of_small_arms.pdf

Arborelius, Ulf P. (1999-2013). Shooting holes in wounding theories: The mechanics of terminal ballistics. Retrieved from
http://www.rathcoombe.net/sci-tech/ballistics/wounding.html

Newgard, Ken. (1992). The physiological effects of handgun bullets: The mechanisms of wounding and incapacitation. Wound Ballistics Review, 1(3): 12-17.
https://drive.google.com/drive/folders/0B_PmkwLd1hmbd3pWYVVJeGlGaFE

Hollerman, J. J., Fackler, M. L., Coldwell, D. M., & Ben-Menachem, Y. (1990). Gunshot wounds: 1. Bullets, ballistics, and mechanisms of injury. American Journal of Roentgenology, 155(4), 685-690.
https://www.ajronline.org/doi/abs/10.2214/ajr.155.4.2119095

Schaefer, John C. (2014-2018). Terminal ballistics. Retrieved from
http://www.frfrogspad.com/terminal.htm
and http://www.frfrogspad.com/terminal2.htm

Gateway to Airguns. (Ed.). (2018). Hunter’s terminal ballistics. [Thread]. Retrieved from
https://www.gatewaytoairguns.org/GTA/index.php?topic=148277

● Some of Bob’s excellent articles on airgun terminal ballistics (some are about slugs but the principles are similar for pellets):
Sterne, Bob [rsterne]. (2020, Apr. 15). The effect of caliber on airgun pellet performance. HardAir Magazine. Retrieved from
https://hardairmagazine.com/ham-columns/the-effect-of-caliber-on-airgun-pellet-performance/

Sterne, Bob [rsterne]. (2020, Jun. 22). Bob Sterne discusses hollowpoint slug design. HardAir Magazine. Retrieved from
https://hardairmagazine.com/ham-columns/bob-sterne-discusses-hollowpoint-slug-design/

Sterne, Bob [rsterne]. (2020, Mar. 17). Airgun pellet penetration – the real story. HardAir Magazine. Retrieved from
https://hardairmagazine.com/ham-columns/airgun-pellet-penetration-the-real-story/

 

[stoti]

Good post with a lot of accurate information. Thank you! I agree that a large hole and the associated damaged is a major factor in killing game. 

However, hydrostatic shock also needs to be considered! The massive dump of energy that causes organ failure or severe damage can and does kill too. Some say the phenomena doesn’t exist, I completely disagree! I’ve seen it happen many, many times. I’ve killed animals that when recovered, had only a tiny entrance wound, no exit wound and almost no blood loss. Upon impact, the animals often drop right where they stood. The internals were turned to mush even though the projectile hadn’t touched them. The damage was done solely from the transfer of energy. I even killed a deer when I was a teenager that I shot where the antlers connected to the skull. The bullet hit the antlers near the skull, the deer dropped where it stood and never moved. When we inspected it, we noticed there was no external damage or blood. Whether the deer had a heart attack, it was the shockwave damaging his brain or spinal cord, I don’t know. I just know he died on the spot and it wasn’t from the wound channel or blood loss. 

I’m not trying to be argumentative at all and I know hydrostatic shock is controversial with some. However, because I’ve seen the effects of hydrostatic shock quite a few times, first hand and know many of you have too, I would suggest that It definitely kills. Like I said, I’m not trying to be argumentative, I’m just sharing a differing point of view for everyone to think about. 

Have a great rest of your weekend. 

Stoti

 

[UncleHoot]

For 50 years, with springers and then pcp's, when the game was in range, I shot them with .177 flat-heads and generic .22 round nose pellets, and the critters all died on impact.

After reading the above, I wonder...am I under-thinking this process?



Kindly Ol' Uncle Hoot

 

[JungleShooter]

After reading the above, I wonder... am I under-thinking this process?

Kindly Ol' Uncle Hoot

No man, you're not. You likely have way more shooting experience, are a much better shot than I am, and you're probably overqualified to kill critters. And not under-thinking the process.

Carry on.

Keep killing'em. Dead is dead.



Matthias

 

[scallen2112]

Good read. But I too am having a hard time believing hydrostatic shock has no or even little effect. I got my first deer on the last day of the year. A small doe. I shot her in the lungs with a 300 grain hollow point out of a Texan Carbine. I watched that deer die, and it was plain as day that she couldn't breath. There was no exit wound (the slug lodged in the far shoulder) and there was not a single drop of blood coming out of that entrance hole. But when I cleaned her, the entire back half of both lungs were a bloody, goopy mess far out from the hole. The shock had ruptured cell walls, vessels, and capillaries, and the hemorrhaging extended several inches from the permanent wound channel. That wasn't caused by just poking a hole in her. If it was, a field point on an arrow would do the same thing. Am I an "expert"? No. But I have to go with what's right there for my eyes to see.

 

[scratchcoobster]

If it was a hole and only a hole (nothing else) that kills, how do you explain blunt force trauma? How do you explain killing an animal with a rock , that not only doesn't penetrate, but creates no hole? It's the damage to vital organs and tissues that kills. This can be accomplished by cutting off the air supply or blood flow, such as using a snare on a rabbit. Trapping an animal and having it bleed to death. Or the caveman way of driving animals over a cliff and having them fall to their death.

Secondly, a hole is not only deadly if it "is in the right place". Put a hole in some living critter and it will likely bleed out or die from infection, without too much concern for where that hole is.

I understand your premise and appreciate the effort involved in creating this series, but don't be too strident on what it is that kills. There are many factors involved (including hydrostatic shock, as mentioned) that need to be considered.

 

[Steveoo]

What he says...(Stoti)

In 1988, a leading English gunsmith attempted to produce a new tiny caliber Deer stalking rifle. The caliber was .170...actually smaller than a .177 pellet. His experimenting revealed, if velocity was super high, it would kill via the shockwave. It worked too but was not universally well received and he later dropped the idea.

More to Ballistics than meets the eye.

 

[JungleShooter]

Friends,

I appreciate the comments.  

Maybe I should have been more explicit to avoid causing confusion, sorry.



That death can occur from many other causes besides a HOLE in the right place -- yeah, I would agree, some people close to me died of Corona. A good whack on the head with the back of a springer rifle will do the blunt force trauma trick. Etcetera. However, when posting at AGN I assumed we all assume we're talking about killing by shooting typical airguns . I guess I took it for granted that we're not talking about 300 grain projectiles, as AGN and other airgun forums separate big bore airguns from the rest as they are not "typical." I'll try to be more clear next time.  



I did mention the low velocities of airguns, and the group of ballisticians that do believe in "hydrostatic shock" say it might occur at or above 2000 fps of impact velocity (at least that's what I read).



When I wrote about putting a HOLE in the critter I did mention brain and heart/lungs -- yet I also mentioned the blood loss from a HOLE in muscle tissue and other organs, and I mentioned septicemia (infection) -- as two ways of killing an animal. The latter might occur after days of suffering. The former could occur rapidly -- if the HOLE is in the right place....



OK, and now I have to stop typing and start shooting at some pestering pigeons. Stay safe in this corona craze.

Matthias

 

[stoti]

Matthias, I hope I didn’t come across as rude or argumentative. I love these posts you share and certainly didn’t want to seem that way. Although the examples I gave were animals I have killed with a centerfire rifle, I believe hydrostatic shock is a phenomenon that can be applied to some of the high power air guns that many of us use too. I don’t know for sure, I’ve never researched it but I would think a .25 caliber, soft lead, hollow point, slug dumping 80+ FPE into a small game animal would have to hydrostatic shock? Like I said, I really don’t know how much energy it takes or if it would be classified as hydrostatic shock in the case of air guns. 

I’ve shared this example before...My son shot a digger squirrel at 135yds with a .25 caliber slug going well over 900fps. The shot hit the squirrel in the abdomen and ripped it almost completely into two pieces. Although there was a huge entrance wound and a huge exit wound, the energy dump is what blew the animal in two pieces. Although I’ve always assumed this explosive damage was considered hydrostatic shock, maybe it’s actually called something else. It’s the same as the massive wound channel that opens quickly and then closes just as quickly when a projectile dumps it’s energy into ballistic gelatin. 

Like I said in my first post, I know hydrostatic shock can be considered by some to be controversial. I never really thought so because I’ve seen it happen so often over the years. Now though, I’m wondering if there is yet another phenomena or if the energy dump that kills is not actually called hydrostatic shock?

I’m going to research hydrostatic shock and see what I can find out. I’ll share what I find if it’s anything important to this discussion.

Have a good one Matthias!

Stoti

 

[JungleShooter]

 Stoti,

you're one of the last guys I'd see as argumentative! Your contributions and interactions are thoughtful and kind — I appreciate meeting people like you here at AGN.



The phenomenon you observed — well, I don't know, maybe there is a different name for it rather than "hydrostatic shock." Like you said, between scientists it's a controversial issue, and I'd assume so much more when we're talking subsonic impact velocities.

But I really don't know the depth of that subject!


I certainly lack the experience that you and many others here have, so I have a lot to learn still.



Thanks for writing. Stay well in this corona craze, Stoti.... So far, my family and I are OK. But Peru's ICU units are all full, so acute corona cases get into a waiting line that might not lead to an ICU bed but to a wooden bed 6 feet under.


Matthias

 

[Odoyle]

I normally try to use the least power to kill. I try to make sure the pellet stays inside the critter. Seems to drop them stone cold dead more effectively from what I have witnessed over the past 45+ years as opposed to zipping right through them to scurry or fly to their deaths in the neighbors property.

 

[LostinTejas]

For 50 years, with springers and then pcp's, when the game was in range, I shot them with .177 flat-heads and generic .22 round nose pellets, and the critters all died on impact.

After reading the above, I wonder...am I under-thinking this process?



Kindly Ol' Uncle Hoot

No. All that just explains what happened. I love the "Energy" debates. In the end, energy moves things, drives things, and breaks things. It is the end all but not how most think it is.

Air guns, arrows, and pistol calibers have a lot in common, they function through destruction, so putting the hole in the right place is critical. There is no hydrostatic shock energy to these, they are just too slow. Hydrostatic injury starts at about the 2300 FPS range.

Not to worry, they work just fine and have since the invention of the lead ball, and that also means the bullet has to physically make a hole in the heart lungs, brain.

Good stuff.

 

[Zebra13]

Gents,

While certainly no expert on the matter, I have a bit of knowledge in regards to terminal ballistics, having written the internal/external/terminal ballistics chapter for my departments police sniper manual, and lectured on same during our sniper schools. And I do apologize as some of my following examples are human, and are, therefore, pretty graphic and shocking, but it is what I know. So with that in mind...

I believe hydrostatic shock, or the temporary wound cavity, is for real. Case in point: A 600 grain arrow from one of my long bows, shot at 180 fps into the cranial ocular vault of a human being is likely going to be fatal, due to the permanent wound cavity (tissue that is destroyed) and the resulting hemmoraging. Hydrostatic shock/temporary wound cavity is not present. Now...take that same cranial ocular vault and send a 308 caliber, 168 grain Sierra BTHP at 2600 fps through it, and it's a completely different ball game. The 168 grain Sierra causes an over pressure situation, caused by hydrostatic shock/temporary wound cavity, that forces the medulla oblongata (brain stem) into the for foramen magnum (the hole in the base of your skull that the spinal cord disappears into), and thoroughly smushes it, which causes a complete and utter shut-down of the central nervous system and the human being surrounding it. 180 degrees away from the medulla oblongata ana-godda-davida thing is the top of the skull, with all of its inherently weak joint lines that kneaded together when we were wee pups. Well, the over-pressure causes those to give way and pop goes the rest of the brain, right out the top.

Hydrostatic shock and the temporary wound channel are alive and well, but require the projectile to have a certain velocity and mass to make it all happen. And...this is a big and...also relative, I believe, is the SIZE OF THE CRITTER YOU'RE SHOOTING!

Hydrostatic shock from a 52 grain, .224 caliber bullet fired from a 220 Swift at 4100 is not going to kill an elephant. For hydrostatic shock to have any part in killing an animal that big would require a projectile of such mass, and at such a velocity, to make actual firing by a human being literally impossible. Critters that big die from CNS interruption, blood loss, or lack of oxygen. Karamojo Bell sent many an elephant to the great beyond with a 7x57 Mauser and 160 grain or so solid bullets directed right into the brain, at velocities that would make most modern rifle hunters yawn. Tissue destruction and a permanent wound cavity were the name of the game.

When you lack sufficient velocity to impart hydrostatic shock...lets say with a handgun round, you get people like Veral Smith of LBT Bullets, and gun writer Ross Seyfried, who, respectively, pioneered and popularized using big bore handgun bullets with as large as meplat as possible to cause the maximum amount of permanent wound cavity damage as possible. And you get hollow points, Black Talons, Hydra Shocks, etc., all designed to destroy tissue through expansion.

Stoti's comments about the digger squirrel bring to mind another ballistic observation I have observed. Mass must have something to do with the splatter factor as well. 40 grain Nosler Ballistic Tips at 3750 fps out of my .223 do bad things to ground squirrels. 55 grain Ballistic Tips out of my 22-250 at 3650 fps are absolutely devastating. Red mist...Kibbles and Bits. That must be the whole energy thing. Stoti... I think you're on to something.

In closing, I don't think, except for the smallest of our quarry, our pellet guns cause much in the way of hydrostatic shock/temporary wound cavity. We'd probably be best choosing our projectiles based on their tissue destruction capabilities. And this kinda makes me wonder why we're not shooting wadcutter type pellets at the majority of our quarry. I mean, the name "wadcutter" kinda makes it obvious, don't it?

Justin

 

[JimNM]

Religion, Politics and Hydrostatic shock...three things I prefer not to talk about. I am usually wrong at least two times a day, and it is still early.

I agree wholeheartedly about the size of target and energy levels being critical to the discussion. The term "over pressure" made me smile. Tissue can only stretch so much before its elasticity is destroyed. My horse wrangler often commented that the hoof is a long way from the heart. IMHO Alphabet org gel does not adequately model the structures and connective tissues present in living targets.

Brain death is only caused by tissue destruction or by oxygen starvation. O2 starvation is caused by loss of hydraulic pressure and/or failure of the gas exchange mechanism in the lung - net effect is the failure to deliver oxygen to the brain.

Colloquially, a DRT (dead right there) shot is said to have hit the "Off switch". A massive upset to the CNS is key to DRT.

The next best is disruption of the pulmonary system. Stop the heart/lung and the brain will follow. One cannot puch a hole through the left rear leg and expect a quick clean kill. Generally, damage above the diaphragm in the core will conclude the event with some rapidity.

Placement is key, given sufficient penetration. Lack either one, and the ethical kill is lost.

 

[ApexPredator]

Zebra13 has a handle on this subject. I've done lots of deer and hog hunting, and have killed many of each over 40+ years. I've used practically every weapon, with the exception of air guns. I will be purchasing my first big bore soon for hunting deer/hogs. From my bow/muzzleloader/handgun hunting experiences, I'll take two big holes through the heart/lungs every time! Head shots, which cause horribly fatal wounds on so called "misses", are not for me. For airgun hunting I plan to shoot the largest slug, with the largest meplat as practical. I'm leaning towards the Dragon Claw .50 for my first.