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Old 12-26-2012, 18:17   #801
uz2bUSMC
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I'll keep playing this game...

Muzzle energy alone is not the sole factor. Also, the .357sig can achieve over 600+ ft lbs...
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Old 12-26-2012, 18:25   #802
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There would indeed have to be a very specical bullet to seperate the first 5 caliblers into one caliber being a lot more effective than the other four???? ya think

Now that number 6. Hmmmm I can see how that caliber might prove to be more effective than the other 5.

44 magmun has close to 1000 ft/lb

.223 about 1300 ft/lb

.308 about 2600 ft/lb

You guys are asking a lot out of theories with little muzzle energy to support them

Rusty
10mm. Most of us regular guys just cannot handle that powerful of a handgun.
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Old 12-26-2012, 18:39   #803
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uz2, hmmm I have not found that 357 sig round yet or the loaded factory round. my 357 sig is 4" barrel.

I will certainly concede that ME is not the whole story. Bullet construction has to transfer that energy. I am saying that the energy contained in the bullet just prior to entry is all the energy there to use.

hunting with FNAR I have certainlly seem evidence of the hydrostatic shock, etc......but not from 600ft/lb. It is my opinion we are talking about rather modest amounts of energy at best.

at 600ft/lb both deer and pigs will make it 75 yds hit thru both lungs. I had a 234# boar shot thru both lungs and bottom of heart with 10mm make it 80 yds.

I am skeptical of any magic at 600 ft/lbs

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Old 12-26-2012, 18:51   #804
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uz2, hmmm I have not found that 357 sig round yet or the loaded factory round. my 357 sig is 4" barrel.

I will certainly concede that ME is not the whole story. Bullet construction has to transfer that energy. I am saying that the energy contained in the bullet just prior to entry is all the energy there to use.

hunting with FNAR I have certainlly seem evidence of the hydrostatic shock, etc......but not from 600ft/lb. It is my opinion we are talking about rather modest amounts of energy at best.

at 600ft/lb both deer and pigs will make it 75 yds hit thru both lungs. I had a 234# boar shot thru both lungs and bottom of heart with 10mm make it 80 yds.

I am skeptical of any magic at 600 ft/lbs

rusty
Your magic words in all of that was "bullet construction", anywho...

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Old 12-26-2012, 19:06   #805
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Digilo, The g20 is pretty decent in the 10 mm. it will help a lot if you strengthen you grip and forearms. That is to increase your split times. Most pistol shooter I know can handle the 10 mm slow fire with g20. agressive high combat grip in g20 will give most shooters .4 second split times. maybe for six shot string on two to the body targets.

in pistol shooting stronger is better period. the 10mm is not a pistol ya fire once a year to qualify.

I have shot matchs with 10mm and Blazer ammo. it is not much over 40 cal and the g20 doesn't not recoil more than major 40.

g20 is a good pistol

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Old 12-26-2012, 19:39   #806
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uz2, I do have them on order. I have not hunted my sig357 yet but I have hunted the below revolver several times with both the 110 gr and 125 gr bullets. I'll still stick by my original post. If you want to put 100-200 pigs in freezer get 10mm.

If you want to cold cock 80# pigs and below use 110 to 125 357 bullets. on 150# pigs IMO not so good. they do expire but you will get the dog out to find them. upto 200yds away in very thick brush. uz2, pigs are tuff.

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Old 12-26-2012, 20:48   #807
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Wow what a debate. It is starting to sound more like a "my dad could beat up your dad" argument though. I'll take a 357 sig, 40sw or 45acp over 9mm shot for shot but I like the low recoil of the 9mm as well. I'm carrying a newly aquired G26 and feel comfortable with it.

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Old 12-26-2012, 20:58   #808
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Wow what a debate. It is starting to sound more like a "my dad could beat up your dad" argument though. I'll take a 357 sig, 40sw or 45acp over 9mm shot for shot but I like the low recoil of the 9mm as well. I'm carrying a newly aquired G26 and feel comfortable with it.
But this thread is not about .40 or 45ACP or the weak 9mm.
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Old 12-26-2012, 21:12   #809
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But this thread is not about .40 or 45ACP or the weak 9mm.
Huh? Why are you singling me out? This thread had for some time now wondered away from the original topic. Did you read any of it?
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Old 12-26-2012, 21:21   #810
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Scoob, it is an interesting thread. made me think a lot, I learned a lot but don't know if it effects real life.

there is an old law enforcement rule....

rule of 3.

1) 3 shoots,

2) 3 yds,

3) 3 seconds.....

the thought at the time was that was the average gun fight. I don't know if it is true. I watched a video of a sheriff shoot himself in the thigh with a 45 acp practicing drawing and firing at three yards.

I don't know if carring is enough to get the job done. I say get some defensive training if ya carry. maybe you already have or maybe you are a top run and gun guy. I am for training no matter if you are a LEO or civilian.

I say it is not the gun/caliber it is the shooter.

Rusty
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Old 12-26-2012, 21:58   #811
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You're looking at it wrong. BPW is messured in p.s.i. Based on that p.s.i you gain a percentage of probability that BPW may assist in incapacitation. This can not be calculated by velocity alone.
But even those who deny the possibility of BPW in handgun calibers admit BPW exists in rifle rounds, eh? That's my baseline starting point on which both sides can agree, yes?
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Old 12-26-2012, 22:18   #812
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Huh? Why are you singling me out? This thread had for some time now wondered away from the original topic. Did you read any of it?
Sorry I didn't mean to single you out. I just believe that 357 sig is a higher performance cartridge in every way vs. 9mm.

45 acp was great when it was developed in 1900 something but I believe it is lowered capacity and added recoil for nothing now, it's just underpowered. Just my opinion.

I like .40sw OK but 357 sig is a higher pressure, higher performance version, although it does make a smaller hole.

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Old 12-26-2012, 23:05   #813
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I like .40sw OK but 357 sig is a higher pressure, higher performance version, although it does make a smaller hole.

Disagree..Somewhat. 500ft/lbs is 500ft/lbs reguard less of stated callibers. Terminal Balistics are a *****. What you do with the available energy at impact is very important. Use a style that over penetrates and you carry energy with the projectile. Use a style that opens to rapidly and you dump the bulk of the energy in a place that may not be the best for tissue damage. Everyone has been looking for the perfect balance for ever.
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Old 12-26-2012, 23:14   #814
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Sorry I didn't mean to single you out. I just believe that 357 sig is a higher performance cartridge in every way vs. 9mm.

45 acp was great when it was developed in 1900 something but I believe it is lowered capacity and added recoil for nothing now, it's just underpowered. Just my opinion.

I like .40sw OK but 357 sig is a higher pressure, higher performance version, although it does make a smaller hole.
Apology accepted. I may have gotten a little uppity myself, but you came into the thread with your 7th post and quoted me in a way that seemed a little condescending. I like 357 sig too but I think you are going overboard.

To break down your post...

First of all your comparison of 357sig and 9mm. To say that 357 out performs 9mm in every way...well 9mm is higher capacity and lower recoil. As I said in the post you quoted, I'd take 357sig over 9 shot for shot but there are other factors to consider. For some, 9mm is just a better option and that isn't even taking into account the difference in price and availability.

As for .45, I am not a huge fan of .45 either but that is mainly because I'm not a fan of the larger guns. The cartridge has proven itself. .45 is a big bullet that does a fine job.

With the .40, I think you are confusing pressure with performance. Pressure can not be compared between two different cartridges to get an outcome. There are other factors. In this case it is a pretty simple comparison since both cartridges have almost identical case volume. The only factor seperating them is the pressures they can sustain.

Pressure is force over an area. The pressure rated in psi (psi meaning pounds per square inch) is the force applied to the chamber, barrel, and bullet. A larger caliber bullet such as the .40 has a larger area so at peak pressures, 35k psi applied to a larger base bullet may be as much or more force than 40k psi applied to a .355 bullet. I'm too lazy to do the math but hopefully you get the idea. There are other factors such as friction but the point is that the operating pressures can be misleading, particularly if the cartridges have a differing case volume or caliber.

Hope this helps and welcome to the forum.

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Old 12-27-2012, 07:59   #815
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But even those who deny the possibility of BPW in handgun calibers admit BPW exists in rifle rounds, eh? That's my baseline starting point on which both sides can agree, yes?
Maybe. I think they might agree on temp cav part but that's about all.
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Old 12-27-2012, 08:11   #816
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.......

Pressure is force over an area. The pressure rated in psi (psi meaning pounds per square inch) is the force applied to the chamber, barrel, and bullet. A larger caliber bullet such as the .40 has a larger area so at peak pressures, 35k psi applied to a larger base bullet may be as much or more force than 40k psi applied to a .355 bullet. I'm too lazy to do the math but hopefully you get the idea. There are other factors such as friction but the point is that the operating pressures can be misleading, particularly if the cartridges have a differing case volume or caliber.
This is an unfortunate confusion which those of us in favour of the BPW hypothesis tend to create by forgetting that all readers do not know that the psi we are talking about is not the psi in the chamber or barrel driving the bullet but the psi of the pressure wave in front of the bullet as it is slowed by the body.

All solid bodies moving through a fluid medium such as air, water, gel or living tissue, create a pressure wave, This is a dynamic effect and not to be confused with the static pressure in the hydraulic system of a car's braking system for instance. In effect, the fluid has to be moved out of the way in a brief time to allow the passage of the solid, whether it is an aeroplane or a bullet. The fluid has mass and therefore force is needed to accelerate it. The pressure immediately in front of the solid is the highest, but because it is pressure in an unconstrained fluid the pressure falls off with distance from there as does the acceleration because with greater distance there is more time for the fluid to move to the side. As a result you can imagine the pressure and acceleration 3D "map" to be rather like a series of mushrooms of increasing sizes stacked on top of each other. The bigger the mushroom the lower the pressure and the acceleration.

One of the important things to remember in a dynamic pressure system is that pressure and acceleration are inseparable. Another is that, in the case of a bullet, the distibution levels of pressure go from nothing and back to nothing very rapidly. Yet another is that the greater the accelration the greater the transmission of energy from the projectile to the fluid. An aeroplane maintains this as a constant state by applying equal and opposite force, but a bullet has only its pre-impact kinetic energy to use.

It is obvious enough that the air displaced by a flying aeroplane or an artillery shell is part of such a huge mass and volume of air that its limits have no effect on the dynamic pressure wave in front of it. A bullet passing through a human or animal body is in very different situation because the dynamic pressure is dependent on the resitance to its production of acceleration. That resistance comes from the tensile strength of the medium and its mass. So a bullet passing close to and parallel with the surface will have greatly reduced pressure on the side towards the surface because the tissue there accelerates away from the bullet path very rapidly with relatively low pressure, relative to the side towards the greater mass of the body.

Although the principle direction of the dynamic pressure wave, or ballistic pressure wave (BPW) in the case of a bullet if we use Courtney's terminology, is forwards, it is still pressure and will propagate through the directions of least resistance. In the extreme we can see shallow crater like wounds in large animals shot with very light very high speed "varmint" bullets. Because of the low level of constraint by the surrounding tissue the peak pressure of such a bullet wound will not be as high as one which penetrates rather further with the same energy. This was one reason why Courtney resticted his testing to hangun bullets which met or exceeded the FBI criteria. Another was that he believed it was important to retain other wounding effects in self defense rounds. Another was probably the underlying belief that any such rapid stop effects depended on a blood pumping effect and that could only be produced by a high pressure spike deep in the body, but that was not part of the hypothesis he was testing.

As far as all those who complain that they don't want a bullet that does not meet the FBI criteria are concerned, they need have no worry because all those tested by the Courtneys met that standard.

Courtney's hypothesis was that the probability of a rapid stop would be closely related to the peak pressure of the psi in front of the bullet. This can be measured with appropriate instrumentation and calculation, but it can also be approximated from the per-impact KE and the penetration depth of the bullet.

It is probably obvious to most here that the greater the expanded diameter of the bullet, the higher the psi in front of it must be, and the shorter the distance it can penetrate. Not so obvious is that the psi in front of the bullet will also be proportional to the square of its speed at impact. A slow and heavy bullet will therefore produce a lower level but more extended over distance and time pressure profile than a faster and lighter bullet of the same KE. This, of course, is subject to the proviso mentioned above that the penetration must be deep enough to provide enough pressure constraint.

The main hypothesis for how this can produce remote brain damage is that such wounds produce a blood pumping effect which deliver a damaging pressure spike to the brain via the blood vessels. It is worth thinking about this with a kind of an analogy. We all know that we can burst a sealed plasic container full of water with a pistol shot. A bullet with too little energy will fail to meet the lower limit and the container will stretch and return to shape unburst. As we move up the energy scale the container will burst with greater and greater drama. We could put quite a lot of weight on the container without bursting it. We could also fire a heavy and slow bullet through it that penetrated both sides without expending much of its KE which would fail to burst it even though the bullet itself has far mor KE that the threshold we seem to have found earlier.

Now imagine we make a lot of small holes in the container and seal them with water resistant sticky tape. Now, if we put weight on the container the tape will give way and the container will squirt little jets of water. If we do the same experiments as before we will probably get slightly different result, quite apart from the slightly higher KE needed to burst the container. This is because some of the dynamic pressure is disipated by squirting water through the holes and so a higher level of KE is needed to produce the earlier pressure at the walls of the containter. Now we have a situation where the bursting effect is dependent on both the KE and the rate at which it is transmitted to the water by the BPW. A fast rate of transmission gives less time for pressure to be disipated via the leaks and a slow rate of transmission gives more time for the pressure to be disipated.

It is not hard to believe that the brain can be damaged by a sudden high pressure pulse of blood and so our interest must turn to how that pulse of blood could be created by a bullet wound remote from the brain. The obvious answer is that if we could suddenly squeeze a bigh enough volume of tissue together, like a large bath sponge, we could squirt a high pressure pulse along blood vessels going to the brain. In fact, this must happen if we shoot someone reasonably center mass because the BPW compresses a volume of tissue. What matters then is how much is enough to have an effect on the brain. Since falling over and bumping into things must all produce such pressure pulses we must be resistant to such things up to some level.

Why is the leaky container a useful analogy? Because lots of blood vessels go in different direction and so only some will carry a "useful" pressure spike to the brain and the others will disipate the pressure. We need a rapid delivery of pressure at a high enough level to do this. It must be one of the random variables in the BPW effect since some bullet tracks will be better placed to pump blood to the brain than others, but all the Courtneys did was make sure that neither heart nor spinal column was hit.

In effect, the Courtneys were doing work on on one shot stops since work on multiple shots would be very difficult to do. The anecdotal evidence was very clear that one shot stops existed but that they were relatively rare and so the Courtneys were never looking for a so called magic bullet but were looking for the way in which the probability of a rapid stop varied with different loads and bullets producing different peak BPW levels. The results were quite clear that, above a particular threshold where there was an extremely small probability of a rapid stop, the probability rose monotonically with increase in peak psi. That is, it did not increase linearly, where twice as much peak psi would produce twice the probability of a rapid stop, but an increase of peak psi produced an increase in the probability of a rapid stop. Above the threshold the rise is quite fast but then the rate of increase falls away until the probility is very high but never certain within the hangun range of KE.

It is curious to see people speculating on whether they can believe that some particular level of KE woud be enough. Their opinions are completely meaningless because the work at that level has been done and exists as fact. There is obviously a lot more that could be done but the fact, as distinct from theory, is that rapid stops exist and and can be demonstrated on a repeatable probabalistic level. Without doing counter experiments, which no one has done for whatever reasons, this fact is indisputable.

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Old 12-27-2012, 08:32   #817
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..... I am for training no matter if you are a LEO or civilian.

I say it is not the gun/caliber it is the shooter.

Rusty
Rusty,
I don't think a single person on the BPW side of this debate would be against your view on training. For the BPW effect to have any chance of working you have to make not just hits but fairly central hits. You can't do that without training. If you hunt through my other posts in other threads you will find a good number where I advocate the importance of training and types of training in particular. But, as uz2bUSMC says somwhere above, this is caliber corners so we start from the assumption that the shooter is able to hit approximately what he is aiming for with the proviso that this is limited by distance, cover and the time to make the shot.

Given that, the shooter is the primary part of the solution but without a reasonably accurate, reliable and powerful pistol he will not be enough to provide the aswer. Since part of that answer is staying alive and since part of staying alive is finishing the fight as quickly as possible, a major part of the answer is that the round you fire has the ability to stop the fight quickly rather than leaving the bad guy to kill people for another 30 minutes before he dies. A 22LR is not very good for this. A .32ACP is a cosiderable handicap and so on. So it is unreasonable to say that it is not the gun/caliber but the shooter since one is not much use without the other. Where is the gun/caliber range we draw the lines between not really good enough, OKish, and good is both difficult and an individual choice, but those line must exist.

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Old 12-27-2012, 18:26   #818
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Ok, lets say every thing stated about 357 sig is the absolute fact. Good guys get the gun and bad guys get the gun.

So here we are. Back to the beginning. Caliber does not matter

Rusty
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Old 12-27-2012, 18:59   #819
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Ok, lets say every thing stated about 357 sig is the absolute fact. Good guys get the gun and bad guys get the gun.

So here we are. Back to the beginning. Caliber does not matter

Rusty
Caliber may matter. While the bad guys are laoding up on the cheap stuff, the good guys are researching and buying the good stuff.
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Old 12-27-2012, 22:01   #820
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This is an unfortunate confusion which those of us in favour of the BPW hypothesis tend to create by forgetting that all readers do not know that the psi we are talking about is not the psi in the chamber or barrel driving the bullet but the psi of the pressure wave in front of the bullet as it is slowed by the body.

All solid bodies moving through a fluid medium such as air, water, gel or living tissue, create a pressure wave, This is a dynamic effect and not to be confused with the static pressure in the hydraulic system of a car's braking system for instance. In effect, the fluid has to be moved out of the way in a brief time to allow the passage of the solid, whether it is an aeroplane or a bullet. The fluid has mass and therefore force is needed to accelerate it. The pressure immediately in front of the solid is the highest, but because it is pressure in an unconstrained fluid the pressure falls off with distance from there as does the acceleration because with greater distance there is more time for the fluid to move to the side. As a result you can imagine the pressure and acceleration 3D "map" to be rather like a series of mushrooms of increasing sizes stacked on top of each other. The bigger the mushroom the lower the pressure and the acceleration.

One of the important things to remember in a dynamic pressure system is that pressure and acceleration are inseparable. Another is that, in the case of a bullet, the distibution levels of pressure go from nothing and back to nothing very rapidly. Yet another is that the greater the accelration the greater the transmission of energy from the projectile to the fluid. An aeroplane maintains this as a constant state by applying equal and opposite force, but a bullet has only its pre-impact kinetic energy to use.

It is obvious enough that the air displaced by a flying aeroplane or an artillery shell is part of such a huge mass and volume of air that its limits have no effect on the dynamic pressure wave in front of it. A bullet passing through a human or animal body is in very different situation because the dynamic pressure is dependent on the resitance to its production of acceleration. That resistance comes from the tensile strength of the medium and its mass. So a bullet passing close to and parallel with the surface will have greatly reduced pressure on the side towards the surface because the tissue there accelerates away from the bullet path very rapidly with relatively low pressure, relative to the side towards the greater mass of the body.

Although the principle direction of the dynamic pressure wave, or ballistic pressure wave (BPW) in the case of a bullet if we use Courtney's terminology, is forwards, it is still pressure and will propagate through the directions of least resistance. In the extreme we can see shallow crater like wounds in large animals shot with very light very high speed "varmint" bullets. Because of the low level of constraint by the surrounding tissue the peak pressure of such a bullet wound will not be as high as one which penetrates rather further with the same energy. This was one reason why Courtney resticted his testing to hangun bullets which met or exceeded the FBI criteria. Another was that he believed it was important to retain other wounding effects in self defense rounds. Another was probably the underlying belief that any such rapid stop effects depended on a blood pumping effect and that could only be produced by a high pressure spike deep in the body, but that was not part of the hypothesis he was testing.

As far as all those who complain that they don't want a bullet that does not meet the FBI criteria are concerned, they need have no worry because all those tested by the Courtneys met that standard.

Courtney's hypothesis was that the probability of a rapid stop would be closely related to the peak pressure of the psi in front of the bullet. This can be measured with appropriate instrumentation and calculation, but it can also be approximated from the per-impact KE and the penetration depth of the bullet.

It is probably obvious to most here that the greater the expanded diameter of the bullet, the higher the psi in front of it must be, and the shorter the distance it can penetrate. Not so obvious is that the psi in front of the bullet will also be proportional to the square of its speed at impact. A slow and heavy bullet will therefore produce a lower level but more extended over distance and time pressure profile than a faster and lighter bullet of the same KE. This, of course, is subject to the proviso mentioned above that the penetration must be deep enough to provide enough pressure constraint.

The main hypothesis for how this can produce remote brain damage is that such wounds produce a blood pumping effect which deliver a damaging pressure spike to the brain via the blood vessels. It is worth thinking about this with a kind of an analogy. We all know that we can burst a sealed plasic container full of water with a pistol shot. A bullet with too little energy will fail to meet the lower limit and the container will stretch and return to shape unburst. As we move up the energy scale the container will burst with greater and greater drama. We could put quite a lot of weight on the container without bursting it. We could also fire a heavy and slow bullet through it that penetrated both sides without expending much of its KE which would fail to burst it even though the bullet itself has far mor KE that the threshold we seem to have found earlier.

Now imagine we make a lot of small holes in the container and seal them with water resistant sticky tape. Now, if we put weight on the container the tape will give way and the container will squirt little jets of water. If we do the same experiments as before we will probably get slightly different result, quite apart from the slightly higher KE needed to burst the container. This is because some of the dynamic pressure is disipated by squirting water through the holes and so a higher level of KE is needed to produce the earlier pressure at the walls of the containter. Now we have a situation where the bursting effect is dependent on both the KE and the rate at which it is transmitted to the water by the BPW. A fast rate of transmission gives less time for pressure to be disipated via the leaks and a slow rate of transmission gives more time for the pressure to be disipated.

It is not hard to believe that the brain can be damaged by a sudden high pressure pulse of blood and so our interest must turn to how that pulse of blood could be created by a bullet wound remote from the brain. The obvious answer is that if we could suddenly squeeze a bigh enough volume of tissue together, like a large bath sponge, we could squirt a high pressure pulse along blood vessels going to the brain. In fact, this must happen if we shoot someone reasonably center mass because the BPW compresses a volume of tissue. What matters then is how much is enough to have an effect on the brain. Since falling over and bumping into things must all produce such pressure pulses we must be resistant to such things up to some level.

Why is the leaky container a useful analogy? Because lots of blood vessels go in different direction and so only some will carry a "useful" pressure spike to the brain and the others will disipate the pressure. We need a rapid delivery of pressure at a high enough level to do this. It must be one of the random variables in the BPW effect since some bullet tracks will be better placed to pump blood to the brain than others, but all the Courtneys did was make sure that neither heart nor spinal column was hit.

In effect, the Courtneys were doing work on on one shot stops since work on multiple shots would be very difficult to do. The anecdotal evidence was very clear that one shot stops existed but that they were relatively rare and so the Courtneys were never looking for a so called magic bullet but were looking for the way in which the probability of a rapid stop varied with different loads and bullets producing different peak BPW levels. The results were quite clear that, above a particular threshold where there was an extremely small probability of a rapid stop, the probability rose monotonically with increase in peak psi. That is, it did not increase linearly, where twice as much peak psi would produce twice the probability of a rapid stop, but an increase of peak psi produced an increase in the probability of a rapid stop. Above the threshold the rise is quite fast but then the rate of increase falls away until the probility is very high but never certain within the hangun range of KE.

It is curious to see people speculating on whether they can believe that some particular level of KE woud be enough. Their opinions are completely meaningless because the work at that level has been done and exists as fact. There is obviously a lot more that could be done but the fact, as distinct from theory, is that rapid stops exist and and can be demonstrated on a repeatable probabalistic level. Without doing counter experiments, which no one has done for whatever reasons, this fact is indisputable.

English
English that is a very interesting post and you put it very well regarding BPW. I am not a BPW supporter, nor am I a detractor. I am still undecided on that subject.

I think you confused my post to be related to external ballistics which it was not. I was reffering to pressure in the internal ballistics sense. Smaller diameter bullets require a higher internal pressure to have the same force applied vs. a larger bullet. The confusion is understandable since the subject was BPW prior to my post.

Last edited by Scoob; 12-27-2012 at 22:08..
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Old 12-27-2012, 22:59   #821
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I'll bet that my .357sig on my hip will do just fine with the job of protecting my life, i'll also bet that my .45 has done so in the past, and that people will still continue to argue pointlessly with a whole lot of theory, and i'll continue to be amused by it.
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Old 12-28-2012, 02:58   #822
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English that is a very interesting post and you put it very well regarding BPW. I am not a BPW supporter, nor am I a detractor. I am still undecided on that subject.

I think you confused my post to be related to external ballistics which it was not. I was reffering to pressure in the internal ballistics sense. Smaller diameter bullets require a higher internal pressure to have the same force applied vs. a larger bullet. The confusion is understandable since the subject was BPW prior to my post.
You are indeed right an I was wrong in what I understood from your post. Sorry about that!

English
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Old 12-28-2012, 06:39   #823
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I'll bet that my .357sig on my hip will do just fine with the job of protecting my life, i'll also bet that my .45 has done so in the past, and that people will still continue to argue pointlessly with a whole lot of theory, and i'll continue to be amused by it.
Good Luck, the last few bad guys I recall had full body armor and ARs. Are you guys watching the same news I am?

I think the bad guys have been doing their research and they are coming up with better ideas then the BWP theory.

Rusty
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Old 12-28-2012, 07:11   #824
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uz2, hmmm I have not found that 357 sig round yet or the loaded factory round. my 357 sig is 4" barrel.

I will certainly concede that ME is not the whole story. Bullet construction has to transfer that energy. I am saying that the energy contained in the bullet just prior to entry is all the energy there to use.

hunting with FNAR I have certainlly seem evidence of the hydrostatic shock, etc......but not from 600ft/lb. It is my opinion we are talking about rather modest amounts of energy at best.

at 600ft/lb both deer and pigs will make it 75 yds hit thru both lungs. I had a 234# boar shot thru both lungs and bottom of heart with 10mm make it 80 yds.

I am skeptical of any magic at 600 ft/lbs

rusty
Not magic, Underwoods New 125gr tested.

On a Chrono, average 5 shots 1568 fps, 682 ft lbs ME

4" barrel Glock. Underwood rates it at 1450/604

Go to 8:45 on the video, or you can watch it all.
The guy tests around 10 different rounds


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Old 12-28-2012, 08:12   #825
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Good Luck, the last few bad guys I recall had full body armor and ARs. Are you guys watching the same news I am?

I think the bad guys have been doing their research and they are coming up with better ideas then the BWP theory.

Rusty
Does anybody know if a 30-30 works against body armor? ( I'm an old guy who still gets spastic at the thought of owning or using an M-16 or variant.)
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