In my opinion you need to match the velocity to the type and weight of bullet you are using and also using the correct bullet for the shot placement you intend to take (where possible). Everyone will have some opinion and or experience of different bullets that work for them but for me as a rough guide, light, fast and rapid expansion bullets for neck/head shooting and heavy, slower controlled expansion for chest. There are some grey areas but as a guide this will work, as for hydrostatic shock, yes it can be a good thing to a point as you are doing a lot of damage in the vital area, but there is a point where you are doing excessive damage and wasting meat that doesn't need to be spoiled. I have played around with a number of bullets and different velocities and found that impact speeds under 2500fps with 165gr nosler bt and partitions cause next to no bruising and still produce a humane kill. I found factory loaded hornady 150gr sst at around 2700fps (from memory) made a mess that was unacceptable, 150gr Sierra gamekings at 2700fps ish work very well for chest shots but useless for neck shots. I am currently using 125gr nosler bt at 2800fps mv and am getting good results on muntjac through to fallow, they work well for neck/head shots and at longer range are good for chest shots, they are giving a bit of bruised meat on the shoulders but have always passed through giving a good wound channel and fast kills, this particular bullet is what's working for me at the moment so I will stick with it. As for the question you asked, an answer is not easily given, make sure you are using a suitable construction of bullet for the shot placement you want and most importantly make sure you can put it where you want to and all will be OK.
What is hydrostatic shock?
- Thread starter Sheprador1973
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CarlW
Well-Known Member
I do find it amusing when someone asks a question about a particular bullet, and they receive replies such as "this fella didn't complain; enough said!", accompanied by a picture of a dead deer.
I had not thought of hydrostatic shock as being confined to or just conducted by the blood carrying capillaries before.
I had just taken it that animals were fairly soggy, overall being 2/3 to 3/4 water including blood. I envisaged the shock wave being transferred by all the tissue and body fluids and that the significant effect was to connect to and zap the CNS, with the tissue rupture as incidental / collateral damage on the way.
Alan
Probably the most accessible write up of this subject is by N Foster in his Effective Game Killing article.
Effective Game Killing
To be honest, I am one of those that makes the mistake of getting hydraulic and hydrostatic mixed up.
I haven't fully bought into it, the hydrostatic part. When I get bang flops, its almost always because I've hit a very specific part of the anatomy that I know controls or significantly influences CNS and hence locomotion. And I can do that with a .243 100gr bullet at 200m or further no worries, so that doesn't fit Foster's criteria of bullet diameter, weight or velocity (its a relatively mild load).
The last couple of deer I shot were with the .308 at around 150m, and they both instantly collapsed. Both had the "junction box" or "fuse box" (aorta / pulmonary arteries / aortic & autonomic nerve pathways) taken out with a very soft, fast expanding bullet (Speer 165gr BTSP) which didn't exit in either case, therefore dumping all of that ~2000ft-lbs right on the lethal spot. When I gralloch the animal like that video of the one I posted a little while ago, the organ destruction is massive, without the irritation of a massive exit hole and peripheral meat all bloodshot and wrecked. If you can put the bullet in that fuse box position, and get the bullet to open and stop, I'm sure there must be one helluva energy wave through the vitals. In the super slow-mo videos, you can see the ripples of energy post-impact in the hide of the animal, when they are hit really hard. There's a good example on a stag with a 7mm Blaser Magnum, showing the shock waves through the front of the torso. It collapsed right there. Hardly surprising.
Foster suggests that the hydrostatic shock puts them down, and the wounding kills them (either direct or through hydraulic wounding like the gel photo earlier). I'm not too fussed, my primary motive is to get them on the deck as close to where they were standing when they were hit as possible, if its one or the other or both doesn't matter.
Its an interesting subject. No substitute for that fuse box shot though, guaranteed bang floppery.
Effective Game Killing
To be honest, I am one of those that makes the mistake of getting hydraulic and hydrostatic mixed up.
I haven't fully bought into it, the hydrostatic part. When I get bang flops, its almost always because I've hit a very specific part of the anatomy that I know controls or significantly influences CNS and hence locomotion. And I can do that with a .243 100gr bullet at 200m or further no worries, so that doesn't fit Foster's criteria of bullet diameter, weight or velocity (its a relatively mild load).
The last couple of deer I shot were with the .308 at around 150m, and they both instantly collapsed. Both had the "junction box" or "fuse box" (aorta / pulmonary arteries / aortic & autonomic nerve pathways) taken out with a very soft, fast expanding bullet (Speer 165gr BTSP) which didn't exit in either case, therefore dumping all of that ~2000ft-lbs right on the lethal spot. When I gralloch the animal like that video of the one I posted a little while ago, the organ destruction is massive, without the irritation of a massive exit hole and peripheral meat all bloodshot and wrecked. If you can put the bullet in that fuse box position, and get the bullet to open and stop, I'm sure there must be one helluva energy wave through the vitals. In the super slow-mo videos, you can see the ripples of energy post-impact in the hide of the animal, when they are hit really hard. There's a good example on a stag with a 7mm Blaser Magnum, showing the shock waves through the front of the torso. It collapsed right there. Hardly surprising.
Foster suggests that the hydrostatic shock puts them down, and the wounding kills them (either direct or through hydraulic wounding like the gel photo earlier). I'm not too fussed, my primary motive is to get them on the deck as close to where they were standing when they were hit as possible, if its one or the other or both doesn't matter.
Its an interesting subject. No substitute for that fuse box shot though, guaranteed bang floppery.
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Foster is probably where I got my overview.
@VSS describes the tissue damage around the wound channel caused by hydraulic pressure which is most likely the ultimate killer...the hydrostatic shock effect is the stun or knock out when the shock wave hits the CNS.
Your Hilar / CNS aim point combines both, which is why bang flop is more consistent and predictable?
Alan
Yup. Hilar, fuse box, junction box, all the same thing.
All mammals have a bunch of nerve pathways running alongside the aorta. Where the aorta and the pulmonary artery are closest, a little in front of and above the heart, in the channel between the two lungs, you also find the autonomic nerve pathways. Destroy that area, and blood supply to and from the lungs, and to and from the legs and all associated muscle, is instantly stopped. The destruction of the autonomic nerves causes all subconscious control over the heart, breathing etc to instantly stop, and it causes the CNS to go into a major short circuit. The shock wave emanating from this area may or may not affect the spinal column, that's the part I'm not sure about. I don't believe my 223 or 243 hits them hard enough for hydrostatic shock, but both will still effect a very fast kill with the right bullet.
Either way, dead runs are 0-3m when this area is hit properly, rather than several tens of metres or a lot more if only the heart is hit, or worse, the rear lungs.
I know that If I lift my point of aim to the high shoulder, I get a very different part of the CNS (brachial plexus) and most likely the underside of the spine. Different mechanism of collapse. There's no dead run either. They're on the floor.
More and more guys here are filming their hunts. Not many are YouTube quality material, but they get shared around. A lot of shooters use magnums, a few of my mates do. By-and-large I'm not seeing that many instant magnum bang flops from hydrostatic shock, on animals that aren't hit exactly where it really counts, in the junction box. They still run. Not as far, but they don't just automatically bang-flop willy nilly cos they got shot with a magnum.
All mammals have a bunch of nerve pathways running alongside the aorta. Where the aorta and the pulmonary artery are closest, a little in front of and above the heart, in the channel between the two lungs, you also find the autonomic nerve pathways. Destroy that area, and blood supply to and from the lungs, and to and from the legs and all associated muscle, is instantly stopped. The destruction of the autonomic nerves causes all subconscious control over the heart, breathing etc to instantly stop, and it causes the CNS to go into a major short circuit. The shock wave emanating from this area may or may not affect the spinal column, that's the part I'm not sure about. I don't believe my 223 or 243 hits them hard enough for hydrostatic shock, but both will still effect a very fast kill with the right bullet.
Either way, dead runs are 0-3m when this area is hit properly, rather than several tens of metres or a lot more if only the heart is hit, or worse, the rear lungs.
I know that If I lift my point of aim to the high shoulder, I get a very different part of the CNS (brachial plexus) and most likely the underside of the spine. Different mechanism of collapse. There's no dead run either. They're on the floor.
More and more guys here are filming their hunts. Not many are YouTube quality material, but they get shared around. A lot of shooters use magnums, a few of my mates do. By-and-large I'm not seeing that many instant magnum bang flops from hydrostatic shock, on animals that aren't hit exactly where it really counts, in the junction box. They still run. Not as far, but they don't just automatically bang-flop willy nilly cos they got shot with a magnum.
enfieldspares
Well-Known Member
Elmer Keith in the 1930s did some experimenting with solid bronze bullets. Not as per today's types with an open tip and so designed to expand but solid like a miniature armor piercing artillery round of that era. He did this to see if velocity alone did in fact kill. AFAIR....it is in "Hell I was there..." he found that it didn't and that all that he observed were holes straight through his quarry that unless a vital part was hit did not collapse and die.
I wonder what velocity those bullets were travelling at and how heavy they were?
enfieldspares
Well-Known Member
From recollection certainly at least 3,00fps and, I think, .22" or .240" calibre. It used to be possible to view an online version of the book.
I guess that is why we use or design bullets to pass through the air with the minimum of loss of energy but then expand and / or fragment on impact with the target to maximise the transfer of energy.
I am surprised though that Elmer Keith's non-expanding bullets had such little effect on a wet body at that velocity, given that even full metal jackets lose all their energy within a few meters of water as per those Private Ryan/myth-busting videos of the AK47 fired underwater across a swimming pool.
Alan
I am surprised though that Elmer Keith's non-expanding bullets had such little effect on a wet body at that velocity, given that even full metal jackets lose all their energy within a few meters of water as per those Private Ryan/myth-busting videos of the AK47 fired underwater across a swimming pool.
Alan
enfieldspares
Well-Known Member
Ah well. Water of course doesn't compress. Whereas I suppose the flesh of an animal can "move out f the way" as it were? So I suppose that that AK46 bullet has a more difficult task.
flying felix
Well-Known Member
This may help your understanding:
When a projectile passes through a body it produces two types of wound channel the permanent and the temporary.
The permanent wound channel is the hole that is produced by it being impacted directly with the projectile.
The temporary wound channel is the hole that is produced by the shock wave. The expansion and contraction that you see in ballistic gel. The temporary wound channel looks very impressive, but only causes real damage on non-elastic tissue. Elastic tissue is able to absorb the expansion. Typical elastic tissues are muscle, lungs, stomach etc. Non elastic are liver, brain, kidneys etc.
This is why the liver was damaged although not hit and the heart showed no damage.
This is also the reason that people like to shoot bottles filled with water to try and demonstrate the effects of gunshots. It does look impressive with the bottle exploding, but bodies don’t react the same.
When a projectile passes through a body it produces two types of wound channel the permanent and the temporary.
The permanent wound channel is the hole that is produced by it being impacted directly with the projectile.
The temporary wound channel is the hole that is produced by the shock wave. The expansion and contraction that you see in ballistic gel. The temporary wound channel looks very impressive, but only causes real damage on non-elastic tissue. Elastic tissue is able to absorb the expansion. Typical elastic tissues are muscle, lungs, stomach etc. Non elastic are liver, brain, kidneys etc.
This is why the liver was damaged although not hit and the heart showed no damage.
This is also the reason that people like to shoot bottles filled with water to try and demonstrate the effects of gunshots. It does look impressive with the bottle exploding, but bodies don’t react the same.
I made use of this phenomena when working in Australia. We were catching a rare wallaby species (around 100 left in the world) and to achieve this, we'd go out at night, spotlight the animal and then shoot it with a .22 WinMag an inch above its head between the ears. The shock would stun it and I'd jump off the ute and run and cover it in a net. Running around the outback at night is one kind of stupid. Making sure that you do not wipe out 1% of the world's species with a single shot is another
enfieldspares
Well-Known Member
Not quite that's only the half part of it.
When a bullet enters the body and creates the temporary wound channel that wound channel then collapses to leave the permanent wound channel and, as it does, a vacuum is created. Which is why you can get all sorts of muck and (usually) bits of thread from uniforms sucked into a wound cavity. Many many years ago I attended a lecture on wounds in the Falklands War. One of the things advised was if you thought you'd be shot was to fight naked to lessen what got sucked into the wound and with as little webbing as possible as webbing aggravated the likelihood of a bullet tumbling of it struck that webbing.
Interestingly there were three main rifle calibres available to the combatants in the Falklands War. 7.62mm NATO, 5.56mm NATO and, in No4 Enfield rifles the good old vintage .303 Mk VII. However, the lecturer said, as nobody from the Falklands Islands Defence Force actually shot anybody that last calibre didn't need to be considered further in the post-conflict wound study. But it was probably, he thought, likely to be the last war, certainly, in which British Forces fought a formal war rather than a guerilla war or anti-terrorist war in which the No 4 rifle was carried by combatants fighting under the British flag.
Shock waves alone, in the air can be deadly. It's the principle of things like thermobaric weapons, fuel-air explosives, some types of barrel bomb etc.
We won't initiate a true shock wave in flesh with a bullet. It's maybe 80% water, and the speed of sound in such is over 4x that of air. Maybe in an inflated lung.
Of course a tremendous pressure pulse can occur, as with the temporary wound cavity, bruised or jellified meat etc, resulting in shock in the sense of knocking out critical nerve plexuses (bang-flop).
Or perhaps travelling through the blood stream from say heart shots, but again, as with lung shots, it rather depends on whether the animal has full or empty lungs, or the beat of the heart, at the time. Maybe accounting for the variable results that we get with these traditional aiming points.
I've had one top-of heart shot (heart itself undamaged) that was instant death, the liver was also quite bruised, my theory is that the hydraulic pulse maybe went into the liver via the hepatic artery, and also travelled up the aorta and into the brain through the carotids. Every other ones always ran a bit, sometimes quite a long way, even with no functioning heart, essentially bled-out. Not that I have any great experience.
It's interesting at the range watching doughnut shaped shock waves travelling downrange with the bullet through a spotting scope under suitable atmospheric conditions. Interesting that that can be enough to concuss a rare wallaby.
We won't initiate a true shock wave in flesh with a bullet. It's maybe 80% water, and the speed of sound in such is over 4x that of air. Maybe in an inflated lung.
Of course a tremendous pressure pulse can occur, as with the temporary wound cavity, bruised or jellified meat etc, resulting in shock in the sense of knocking out critical nerve plexuses (bang-flop).
Or perhaps travelling through the blood stream from say heart shots, but again, as with lung shots, it rather depends on whether the animal has full or empty lungs, or the beat of the heart, at the time. Maybe accounting for the variable results that we get with these traditional aiming points.
I've had one top-of heart shot (heart itself undamaged) that was instant death, the liver was also quite bruised, my theory is that the hydraulic pulse maybe went into the liver via the hepatic artery, and also travelled up the aorta and into the brain through the carotids. Every other ones always ran a bit, sometimes quite a long way, even with no functioning heart, essentially bled-out. Not that I have any great experience.
It's interesting at the range watching doughnut shaped shock waves travelling downrange with the bullet through a spotting scope under suitable atmospheric conditions. Interesting that that can be enough to concuss a rare wallaby.
Cumbrian 1
Well-Known Member
Kevin Robertson the vet who wrote the "Perfect Shot" series had an additional theory on big game bang/flops which was as the heart valve is either full or empty every other second a bullet hitting an empty valve makes a hole in the heart which then causes death from blood loss but not instantly, hit a chamber full of blood and it will literally explode bringing on an instantaneous (or very nearly) collapse of the animal.
FISH BOY
Well-Known Member
Must admit, Ive always been interested in this with regards to an HMR rather than a centrefire, as often rabbits either show massive damage or absolutely no sign of entry or exit wounds and look literally like they have died of shock.
On the flip side seen .243 BTs literally gralloch foxes.
On the flip side seen .243 BTs literally gralloch foxes.
Shock wave through an almost liquid mass
It doesn't need to be linked to circulatory system volume or heart beat IMO
Along similar principles to head injuries where the impact is at the back of the head but the hematoma is found on the front of the head due to the brain slamming into the skull.
Get hit by something doing 3000fps and the shock wave can incapacitate and kill without blood loss on CNS destruction
Blunt force trauma
It doesn't need to be linked to circulatory system volume or heart beat IMO
Along similar principles to head injuries where the impact is at the back of the head but the hematoma is found on the front of the head due to the brain slamming into the skull.
Get hit by something doing 3000fps and the shock wave can incapacitate and kill without blood loss on CNS destruction
Blunt force trauma
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