Let's start with this statement by CraigC:
""I automatically disregard the arguments of those who remain stuck on kinetic energy in a discussion about big bore revolvers. For it is easy to assume that they do not have a true understanding of how these big, heavy bullets work. All it takes is five minutes looking at ballistics tables to understand that if the lowly 45Colt blackpowder load consisting of a 255gr cast bullet at 900fps and producing a measly 450ft-lb's of energy will kill any deer that walks just as dead as a 165gr .30-06 with vastly higher energy figures, then maybe something else is at work other than energy. Which, as I stated, is FAR too dependent upon velocity. Something which the big sixgun does NOT have an abundance of."
I've wondered about a way to quantify the effect of big bore revolvers. It seems that what ever the effect, it seems to accelerate geometrically in caliber from .40" up. The .475, 500's and .510s seem to kill WAY more effectively then they should. Same seems to be true of the .41 and .429.
The best explanation I've heard is the heavy for caliber bullets are longer, and since they yaw and roll as they pass through the target, the increase in bullet diameter and length increases the effectiveness geometrically.
This sort of jives with the increase in a cylinder's external contact surface being geometrically related to increases in diameter and length.
The final factor is the increase in bullet weight has a relationship to speed through the target. The higher the weight, the less it reduces speed as it goes through a liquid medium. This is sort of a reverse measurement of
KE. The heavier bullet penetrates at a higher speed, and maintains that speed through the target. The consequence is the yaw and roll are increased due to the increase in resistance, transfering more energy to the target, and creating a larger wound channel then the caliber might explain.
One other observation:
While I agree with the effectiveness of CraigC's comment/observation, and that combination has always been my idea of the threshold for effective
rounds, the heavier calibers do have serious Kenetic Energy, but it is caused by bullet weight, and this seems to have a geometric effect on energy figures, as does velocity.
Don't really know how to plug the variables into an equation that can factor all of this, and give a comparable value.
Taylors KO theory, though designed for rifles, seems to sort of give reasonable results.
Kind of wish there was something other then the guys on the ranch yelling,
"Damn! That .500JRH hits like a .375 H&H rifle!"
Or:
"We can't explain it, but the 525 grain LFN's at 1100 fps from BuffaloBore
hit and kill like Thor's Hammer!"
What I'm trying to do is build some sort of awareness that there is a HUGE difference between a .429" magnum, and a .510" caliber, even though the actual measurement is tiny.
One other thought.
When you hit a fluid surface you have severe penetration problems as the impact point increases geometrically. In other words penetrating the surface tension/skin of an object with
a needle is far easier then doing so with a .500" bullet. The amount of energy required to break through a surface of fluid increases geometrically as the diameter of the contact area increases.
I suspect deacceleration also increases geometrically as the contact point surface increases. In other words as the surface contact area increases, the amount of force required to get through
the fluid, and maintain speed requires geometrically increasing energy to breach the barrier.
I keep thinking of the sabots designed with tungstun spikes to breach armour fired from cannons. 5000 fps for a spike maybe a 1/2 inc in diameter, or less, that relies on a narrow contact point to breach the barrier,
but a large wound is created by the yaw and roll of the 6" spike once it enters the target.
""I automatically disregard the arguments of those who remain stuck on kinetic energy in a discussion about big bore revolvers. For it is easy to assume that they do not have a true understanding of how these big, heavy bullets work. All it takes is five minutes looking at ballistics tables to understand that if the lowly 45Colt blackpowder load consisting of a 255gr cast bullet at 900fps and producing a measly 450ft-lb's of energy will kill any deer that walks just as dead as a 165gr .30-06 with vastly higher energy figures, then maybe something else is at work other than energy. Which, as I stated, is FAR too dependent upon velocity. Something which the big sixgun does NOT have an abundance of."
I've wondered about a way to quantify the effect of big bore revolvers. It seems that what ever the effect, it seems to accelerate geometrically in caliber from .40" up. The .475, 500's and .510s seem to kill WAY more effectively then they should. Same seems to be true of the .41 and .429.
The best explanation I've heard is the heavy for caliber bullets are longer, and since they yaw and roll as they pass through the target, the increase in bullet diameter and length increases the effectiveness geometrically.
This sort of jives with the increase in a cylinder's external contact surface being geometrically related to increases in diameter and length.
The final factor is the increase in bullet weight has a relationship to speed through the target. The higher the weight, the less it reduces speed as it goes through a liquid medium. This is sort of a reverse measurement of
KE. The heavier bullet penetrates at a higher speed, and maintains that speed through the target. The consequence is the yaw and roll are increased due to the increase in resistance, transfering more energy to the target, and creating a larger wound channel then the caliber might explain.
One other observation:
While I agree with the effectiveness of CraigC's comment/observation, and that combination has always been my idea of the threshold for effective
rounds, the heavier calibers do have serious Kenetic Energy, but it is caused by bullet weight, and this seems to have a geometric effect on energy figures, as does velocity.
Don't really know how to plug the variables into an equation that can factor all of this, and give a comparable value.
Taylors KO theory, though designed for rifles, seems to sort of give reasonable results.
Kind of wish there was something other then the guys on the ranch yelling,
"Damn! That .500JRH hits like a .375 H&H rifle!"
Or:
"We can't explain it, but the 525 grain LFN's at 1100 fps from BuffaloBore
hit and kill like Thor's Hammer!"
What I'm trying to do is build some sort of awareness that there is a HUGE difference between a .429" magnum, and a .510" caliber, even though the actual measurement is tiny.
One other thought.
When you hit a fluid surface you have severe penetration problems as the impact point increases geometrically. In other words penetrating the surface tension/skin of an object with
a needle is far easier then doing so with a .500" bullet. The amount of energy required to break through a surface of fluid increases geometrically as the diameter of the contact area increases.
I suspect deacceleration also increases geometrically as the contact point surface increases. In other words as the surface contact area increases, the amount of force required to get through
the fluid, and maintain speed requires geometrically increasing energy to breach the barrier.
I keep thinking of the sabots designed with tungstun spikes to breach armour fired from cannons. 5000 fps for a spike maybe a 1/2 inc in diameter, or less, that relies on a narrow contact point to breach the barrier,
but a large wound is created by the yaw and roll of the 6" spike once it enters the target.
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