afcarry
Regular Member
At the risk of starting an argument I am going to start a thread about caliber selection since at our last meeting there was a brief discussion on the topic. Unfortunately, I will be going geek with some ballistics as I understand the topic, so comments are always welcome. Hopefully I wont go too much into it and become boring.
As you may or may not know, I do change my carry weapon with the time of year, and thus change my caliber of choice accordingly. But first, I have to give some background. When I carry in civilian clothes, my intent is not to kill any individual in the interest of self defense. Ever. The worst I would ever attempt to do is incapacitate. Ending somebody's life is an unfortunate but somewhat common result of this, however, it is not the result sought.
There are many theories or schools of thought on the topic of ballistics, and the one I most commonly subscribe to is the pressure wave hypothesis. This simply means that other factors being equal, bullets producing larger pressure waves incapacitate more rapidly than bullets producing smaller pressure waves. This does not necessarily mean that the biggest bullet will always have a greater effect, but rather the bullet that transfers more energy will have a more noticeable (and usually faster) result. So begins the argument of 9mm v .45ACP. Wave magnitude falls off with increasing distance from the point of origin unless reflected by a boundary or confined to an internal structure. An internal pressure wave created in the thoracic cavity will be reflected multiple times by the sides of the cavity. Since pressure wave magnitude is inversely proportional to penetration depth, cutting penetration in half doubles the pressure, if kinetic energy is the same. However, the potential for increased incapacitation is limited, because the wave must be created inside soft tissue and close to major blood vessels or vital organs to have its effect. A bullet that barely penetrates the thoracic cavity has little effect. Incapacitation effects are reduced for penetration depths below 9.5 inches.
The 9mm 124 grain bullet from DoubleTap Ammo shot at 1295fps from a Glock 19 resulted in just under 750 PSI pressure wave, which will probably cause brain damage, and - assuming you hit center mass - will cause a drop in approximately 7 seconds. The .40S&W 150 grain bullet from DoubleTap Ammo shot at 1275fps from a Glock 23 resulted in just over 800 PSI pressure wave, which will also probably cause brain damage, and - assuming again you hit center mass - will cause a drop in approximately 6 seconds. These are all great results, but the thing to keep in mind is that these are all penetration tests in pure unclothed flesh simulate. Come winter time, your average John Doe will probably not be wearing a tank top. Hollow points act as cookie cutters, if you will, turning the best of the best hollow points into non-expanding ball ammunition when coming into contact with jackets, shirts, overalls, snow pants, etc. This fact greatly simplifies the argument, since there is no need for consideration of weight retention, expansion rate, or any of the other benefits of hollow point bullets.
In winter time, you have to (or at least, I do) change your thought process to accommodate the climate. In the winter time your body in an attempt to remain warm will create more cardiovascular constriction - there will be less blood flow at any given point in the body. This will delay the processes of traumatic shock, hemorrhagic shock and exsanguination. This results in another ballistic school of thought: The "Big Hole Theory." Every Cro-Magnon man, woman and child has believed since the beginning of time that bigger is better. In this case, I also believe that to be true. If all of my ammunition is ball ammunition, I would rather have a magazine full of big balls. There are no fantastic numbers to display here, there are no statistics on cold weather shootings, and unfortunately, the effort required to go through all coroner's records of shooting to see the difference in terminal results by season is far more then any of us that I know of are willing exert.
So In the winter, I carry a .45ACP. In the summer I carry a .40S&W, and I am confident that at any given time of year, I am properly equipped to do whatever necessary to defend myself and my family in the most efficient manner possible, and I encourage you all to as well if you don't already.
As you may or may not know, I do change my carry weapon with the time of year, and thus change my caliber of choice accordingly. But first, I have to give some background. When I carry in civilian clothes, my intent is not to kill any individual in the interest of self defense. Ever. The worst I would ever attempt to do is incapacitate. Ending somebody's life is an unfortunate but somewhat common result of this, however, it is not the result sought.
There are many theories or schools of thought on the topic of ballistics, and the one I most commonly subscribe to is the pressure wave hypothesis. This simply means that other factors being equal, bullets producing larger pressure waves incapacitate more rapidly than bullets producing smaller pressure waves. This does not necessarily mean that the biggest bullet will always have a greater effect, but rather the bullet that transfers more energy will have a more noticeable (and usually faster) result. So begins the argument of 9mm v .45ACP. Wave magnitude falls off with increasing distance from the point of origin unless reflected by a boundary or confined to an internal structure. An internal pressure wave created in the thoracic cavity will be reflected multiple times by the sides of the cavity. Since pressure wave magnitude is inversely proportional to penetration depth, cutting penetration in half doubles the pressure, if kinetic energy is the same. However, the potential for increased incapacitation is limited, because the wave must be created inside soft tissue and close to major blood vessels or vital organs to have its effect. A bullet that barely penetrates the thoracic cavity has little effect. Incapacitation effects are reduced for penetration depths below 9.5 inches.
The 9mm 124 grain bullet from DoubleTap Ammo shot at 1295fps from a Glock 19 resulted in just under 750 PSI pressure wave, which will probably cause brain damage, and - assuming you hit center mass - will cause a drop in approximately 7 seconds. The .40S&W 150 grain bullet from DoubleTap Ammo shot at 1275fps from a Glock 23 resulted in just over 800 PSI pressure wave, which will also probably cause brain damage, and - assuming again you hit center mass - will cause a drop in approximately 6 seconds. These are all great results, but the thing to keep in mind is that these are all penetration tests in pure unclothed flesh simulate. Come winter time, your average John Doe will probably not be wearing a tank top. Hollow points act as cookie cutters, if you will, turning the best of the best hollow points into non-expanding ball ammunition when coming into contact with jackets, shirts, overalls, snow pants, etc. This fact greatly simplifies the argument, since there is no need for consideration of weight retention, expansion rate, or any of the other benefits of hollow point bullets.
In winter time, you have to (or at least, I do) change your thought process to accommodate the climate. In the winter time your body in an attempt to remain warm will create more cardiovascular constriction - there will be less blood flow at any given point in the body. This will delay the processes of traumatic shock, hemorrhagic shock and exsanguination. This results in another ballistic school of thought: The "Big Hole Theory." Every Cro-Magnon man, woman and child has believed since the beginning of time that bigger is better. In this case, I also believe that to be true. If all of my ammunition is ball ammunition, I would rather have a magazine full of big balls. There are no fantastic numbers to display here, there are no statistics on cold weather shootings, and unfortunately, the effort required to go through all coroner's records of shooting to see the difference in terminal results by season is far more then any of us that I know of are willing exert.
So In the winter, I carry a .45ACP. In the summer I carry a .40S&W, and I am confident that at any given time of year, I am properly equipped to do whatever necessary to defend myself and my family in the most efficient manner possible, and I encourage you all to as well if you don't already.