Hi,
I'm new to this forum but have been reading on the side line for a long time. As Madis wrote earlier i find the forum very sober. I like the way people share their experience and curiosity.
About the subject - Nathan Forster never wrote that 2600 fps would be a cut off for DRT behaviour. Noor did i write that hydrostatic shock causes istant death.
Just to clarify: Hydrostatic Shock means:
- Hydro = water
- Static = electrical interference (not as suggested earlier in this threat something lacking motion)
It is fluid particles between the hide and the ribcage accelerated as a shock wave by a strking bullet caused by the energy transfer. This schock wave interrupts the electrical signals send between the brain and the spine causing the animal to lose consciousness. This effect makes the hunter believe that the animal is DRT... in reality the animal is knocked unconsciouss and bleeds to death before it can recover.
Hydrostatic shock occours as a general rule at impact velocities above 2600fps (it depends on caliber and bullet design)
It is very important to understand that the kenetic energy a bullet carries only exists as a potential. If the bullet by design, impact velocity, target resistance etc. fails to expand or fragment it will not be able to transfer the potential energy. This is why some bulets, calibers, velocity combinations works perfectly on some species and fail to do so on other.
What Nathan Forster stresses is the importance of delivering what I call "Rifle Effect". The rifle effect is what seperates the rifle from handguns - in short velocity! Here the general cut off point is 2000 fps unless you are using frangible bullets (ELD-M, TMK etc.). If a tough bullet drops below 2000fps you will often see a dramatical drop in performance because the wounding gradualy approaches the performance of a handgun. So why is it 2000 fps?
2000 fps is the general cut off point for initiating Hydraulic Shock (not to be confused with hydrostatic shock). Hydraulic Shock is rifle effect - this is the effect that seperates rifles from handguns - caused by velocity.
If using monolythic bullets as Barnes TSX/TTSX, Horandy GMX etc. the above cut off point may be as high as 2400 fps due to the very tough bullet design that prrevents it from expanding and transfering it's energy when velocity drops.
What Nathan Forster whants is fast killing. To be sure an animal is DRT one must aim for the CNS - that be the brain, neck og auotomus plexus. However the primary target zone for the hunter should be the fast bleeding organs - lungs, lever, heart in that order. The heart is not the fastest bleeding organ as many mistakenly think. A heart shot animal can run up to 300 meters...
The lungs are the biggets organ of the three. They consists of very soft and easy destroyable tissue and a lot of blood flows through them. It is a large target - also horizontal wich makes it forgiving due to wind drift errors.
If the hunter uses a caliber and bullet of sound design, matched the animal and shooting distance the hydraulic shock will secure a large wound channel through the lungs. The best way to observe this is by meassuring the diameter of the wound/bruising. This should be at least twice the size of the expanded caliber and preferably more. In soft tissue (lungs) wounds from a 308W with a soft bullet design can be as big 7.5" in diameter. The wound will be caused by the mechanical / direct contact between the bullets and the tissue. This also covers bullet and bone fragments. Further more the wound channel will consists for the temporary portion wich is causes by the indirect contact - also called hydraulic shock. This is what Nathan Forster refers to as "disproportionat to caliber wounding" - meaning the wound channe being larger than the expanded caliber.
In civil terms hydraulic shock is refered to as "water hammer effect". The best way to understand the phenomenen is to first slowly drop your hand into water and next slam it has hard as you can. Wich of the two heart the most? This also gives one the idea of the realtionship between penetration and velocity. Many people mistankenly thinks that lower velocity equals less penetration and higher velocity deeper penetration - but it is the other way around. A bullet that fails to expand due to low impact velocity will not be able to transfer its energy - therefor it will penetrate deeper.
To sum it up - Nathan do not seek DRT behaviour noor does he chase hydrostatic shock. He is just describing it as being one of the effects of terminal ballistics.
On the other hand he stresses the importans of hydraylic shock and pleads that hunters matches the caliber, bullet weight, design, impact velocity and expected target resistance with 90% of the species you are hunting. If you fall out for the 90% the hunter must be very very thorgough with bullet placement.
As an example I hunt a lot in Germany, culling fallow and roe deer (does and calfs). More than 90% of the animals I shoot is within these two species and sizes. Sometimes an opportunity occours to take red deer or hogs - both of them may weigh up to 150-200 kg. Never the less I still use my 6.5x55 with a 147gr Dynamic Research Tech. bullet because it works so well within the 90% rule on the distances I am are able to shoot at. Is it too small for a large boar or stack - yes propably! Can it be done? deffently with all my focus being on bullet placement.
This last rule of thumb is my best advice when chossing, rifle, caliber and bullet.
Another examble is from Africa. Several of my friends go culling on large farm in Namibia twice a year. All of them shoot 308W wich by definition is to small for african hunting. But when asked what they would primarily be hunting they answered oryx and blesbuck. Single eland and hartebeest could be taken out as well - but would fall in to the lasst 10% Given that the weight of the primarely hunted species are no bigger than scandinavian red deer -and after learning from their experiences from previous trips I suggested loading their 308W with 180gr Nosler Partitions. This has proved to be very very effective - so effective that the PH on the farm now recomends this combination. But again when encountering a large animal as an eland the hunter must show exceptional disciplin and be very thorough with bullet placement.
As a closing comment I will say that I have no shares in Nathan Forsters business. I do work professionaly with external and terminal ballistics, and in that perspective I find his work very interesting and thorough. I am really not trying to lecture people in here since I have the outmost respect for experience in general. I do know though that termimal ballistics is complicated to understand and therefor a lot of misconceptions occour caused by confirmation bias and/or things just taken out of context.
I hope the above have been informative and that I haven't offended anyone. I fo so it has never been my intention.
All the best!
J.
I'm new to this forum but have been reading on the side line for a long time. As Madis wrote earlier i find the forum very sober. I like the way people share their experience and curiosity.
About the subject - Nathan Forster never wrote that 2600 fps would be a cut off for DRT behaviour. Noor did i write that hydrostatic shock causes istant death.
Just to clarify: Hydrostatic Shock means:
- Hydro = water
- Static = electrical interference (not as suggested earlier in this threat something lacking motion)
It is fluid particles between the hide and the ribcage accelerated as a shock wave by a strking bullet caused by the energy transfer. This schock wave interrupts the electrical signals send between the brain and the spine causing the animal to lose consciousness. This effect makes the hunter believe that the animal is DRT... in reality the animal is knocked unconsciouss and bleeds to death before it can recover.
Hydrostatic shock occours as a general rule at impact velocities above 2600fps (it depends on caliber and bullet design)
It is very important to understand that the kenetic energy a bullet carries only exists as a potential. If the bullet by design, impact velocity, target resistance etc. fails to expand or fragment it will not be able to transfer the potential energy. This is why some bulets, calibers, velocity combinations works perfectly on some species and fail to do so on other.
What Nathan Forster stresses is the importance of delivering what I call "Rifle Effect". The rifle effect is what seperates the rifle from handguns - in short velocity! Here the general cut off point is 2000 fps unless you are using frangible bullets (ELD-M, TMK etc.). If a tough bullet drops below 2000fps you will often see a dramatical drop in performance because the wounding gradualy approaches the performance of a handgun. So why is it 2000 fps?
2000 fps is the general cut off point for initiating Hydraulic Shock (not to be confused with hydrostatic shock). Hydraulic Shock is rifle effect - this is the effect that seperates rifles from handguns - caused by velocity.
If using monolythic bullets as Barnes TSX/TTSX, Horandy GMX etc. the above cut off point may be as high as 2400 fps due to the very tough bullet design that prrevents it from expanding and transfering it's energy when velocity drops.
What Nathan Forster whants is fast killing. To be sure an animal is DRT one must aim for the CNS - that be the brain, neck og auotomus plexus. However the primary target zone for the hunter should be the fast bleeding organs - lungs, lever, heart in that order. The heart is not the fastest bleeding organ as many mistakenly think. A heart shot animal can run up to 300 meters...
The lungs are the biggets organ of the three. They consists of very soft and easy destroyable tissue and a lot of blood flows through them. It is a large target - also horizontal wich makes it forgiving due to wind drift errors.
If the hunter uses a caliber and bullet of sound design, matched the animal and shooting distance the hydraulic shock will secure a large wound channel through the lungs. The best way to observe this is by meassuring the diameter of the wound/bruising. This should be at least twice the size of the expanded caliber and preferably more. In soft tissue (lungs) wounds from a 308W with a soft bullet design can be as big 7.5" in diameter. The wound will be caused by the mechanical / direct contact between the bullets and the tissue. This also covers bullet and bone fragments. Further more the wound channel will consists for the temporary portion wich is causes by the indirect contact - also called hydraulic shock. This is what Nathan Forster refers to as "disproportionat to caliber wounding" - meaning the wound channe being larger than the expanded caliber.
In civil terms hydraulic shock is refered to as "water hammer effect". The best way to understand the phenomenen is to first slowly drop your hand into water and next slam it has hard as you can. Wich of the two heart the most? This also gives one the idea of the realtionship between penetration and velocity. Many people mistankenly thinks that lower velocity equals less penetration and higher velocity deeper penetration - but it is the other way around. A bullet that fails to expand due to low impact velocity will not be able to transfer its energy - therefor it will penetrate deeper.
To sum it up - Nathan do not seek DRT behaviour noor does he chase hydrostatic shock. He is just describing it as being one of the effects of terminal ballistics.
On the other hand he stresses the importans of hydraylic shock and pleads that hunters matches the caliber, bullet weight, design, impact velocity and expected target resistance with 90% of the species you are hunting. If you fall out for the 90% the hunter must be very very thorgough with bullet placement.
As an example I hunt a lot in Germany, culling fallow and roe deer (does and calfs). More than 90% of the animals I shoot is within these two species and sizes. Sometimes an opportunity occours to take red deer or hogs - both of them may weigh up to 150-200 kg. Never the less I still use my 6.5x55 with a 147gr Dynamic Research Tech. bullet because it works so well within the 90% rule on the distances I am are able to shoot at. Is it too small for a large boar or stack - yes propably! Can it be done? deffently with all my focus being on bullet placement.
This last rule of thumb is my best advice when chossing, rifle, caliber and bullet.
Another examble is from Africa. Several of my friends go culling on large farm in Namibia twice a year. All of them shoot 308W wich by definition is to small for african hunting. But when asked what they would primarily be hunting they answered oryx and blesbuck. Single eland and hartebeest could be taken out as well - but would fall in to the lasst 10% Given that the weight of the primarely hunted species are no bigger than scandinavian red deer -and after learning from their experiences from previous trips I suggested loading their 308W with 180gr Nosler Partitions. This has proved to be very very effective - so effective that the PH on the farm now recomends this combination. But again when encountering a large animal as an eland the hunter must show exceptional disciplin and be very thorough with bullet placement.
As a closing comment I will say that I have no shares in Nathan Forsters business. I do work professionaly with external and terminal ballistics, and in that perspective I find his work very interesting and thorough. I am really not trying to lecture people in here since I have the outmost respect for experience in general. I do know though that termimal ballistics is complicated to understand and therefor a lot of misconceptions occour caused by confirmation bias and/or things just taken out of context.
I hope the above have been informative and that I haven't offended anyone. I fo so it has never been my intention.
All the best!
J.
. But with all that overwhelming information, I prefer to use a cartridge/bullet combination that I believe can reach vitals regardless of how the animal is facing. I also want it to exit, leave a good blood trail and I limit my shots to under 300 yards (prefer much less). I have found some animals are DRT from a kill shot and some run; there seems to be no consistent reason as to when or why. If the animal doesn't want to go down immediately, I keep shooting until it understands I am serious.
