dennishoddy
Moderator
I have just spent 4 hours of reading about terminal ballistics by Rathcoombe.
I'm about 1/3 of the way through it.
I didn't know exactly where to post it, as it is primarily about the effects of bullets on game animals, but it got so involved into the science of the bullet and its terminal performance, on flesh, organs and the effects, that it needed to be posted here.
The discussion has layed to rest many misconceptions about bullets, velocity, knock down, penetration, and so on that have been presented to us by gun writers so often that we take it as gospel.
Rathcoombe takes each subject and dissects it a piece at a time. Its written with total scientific background, and presented as such with graphs, etc. to demonstrate the point.
I'll first post his resume, and then links to the study. Mix up a big jug of iced tea and get ready to become informed.
No subject in the firearms industry generates more print or heat than terminal performance. In the last fifteen years this issue has even become one of considerable moment with federal agencies, the FBI particularly, leading to the decision to replace entire arsenals of sidearms. Similarly, within the commercial industry we have seen the development of numerous, and occasionally exotic, bullet designs based upon various theories of wounding behavior. Some have worked well, while others have not. But for the most part, shooters and many in the firearms community still do not understand why these things work or fail. My purpose in this study is to examine what we do know and to reconsider the theories which attempt to account for the observed performance. I intend to cover the entire field of terminal ballistics controversy as fairly as possible, but I do have some very definite conclusions of my own which I believe I can explain and defend to the satisfaction of most. Furthermore, I will offer some criticism of the popular formulas for calculating terminal performance and suggest a couple which may provide a real estimate of absolute performance on game (not just a relative comparison to other loads). Although this discussion is intended for the sportsman, I will include material and argument which is of interest to the individual using small arms for self-defense or in police or military applications.
A brief word about my background is warranted. I am a mechanical engineer by profession and employed in the defense industry as an analyst and designer of anti-armor lethal mechanisms (ie, warheads and penetrators). Terminal ballistics is both my hobby and my profession. On the job I use a computational tool known as a "hydrocode" called CTH, which was developed by Sandia National Laboratory, to perform penetration analyses, along with code that I have written for specific applications. My knowledge and studies cover the entire spectrum of penetration mechanics from small arms to high explosive shaped charges. I have extensively read the best forensic studies of bullet behavior, as well as the classic works on field performance by Whelen, Baker, Selous, Taylor, O'Connor, etc. While I freely admit that I haven't personally shot a great number of game animals, I have witnessed others being shot and examined still more post-mortem, to confirm or refute by my own experience the published observations and pontifications of hunters and firearms pundits. I try not to speak dogmatically on subjects beyond my ken, but where the concensus of thought by sage and seasoned scientists and hunters tends toward a clear conclusion, I am not hesitant to assert it.
I believe in being forthright, so I will jump in with both feet and state the premise of my own theory of terminal ballistics. The title of this article is a hint. Plainly stated, I maintain that the effect of bullets upon living targets is caused by the wound track made by the bullet. Now, before you accuse me of being a wise guy, recall that most theoretical explanations of wounding that are batted about in the shooting community are tied to the kinetic energy or momentum or some other such physical quantity of the bullet which is "transferred" or imparted to the target. My theory recognizes these characteristics, but relies upon a fundamentally different premise, which is that two physically equivalent wound tracks in a game animal will have an equivalent effect, no matter how different were the kinetic energies or other physical attributes of the bullets which caused them. There are some extremely rarely encountered exceptions to the general rule, but for most purposes the hole caused by a bullet is its only measure of lethality.
http://www.rathcoombe.net/sci-tech/ballistics/mechanics.html
When you get done with this part, there will be a link to the next. Enjoy!
I'm about 1/3 of the way through it.
I didn't know exactly where to post it, as it is primarily about the effects of bullets on game animals, but it got so involved into the science of the bullet and its terminal performance, on flesh, organs and the effects, that it needed to be posted here.
The discussion has layed to rest many misconceptions about bullets, velocity, knock down, penetration, and so on that have been presented to us by gun writers so often that we take it as gospel.
Rathcoombe takes each subject and dissects it a piece at a time. Its written with total scientific background, and presented as such with graphs, etc. to demonstrate the point.
I'll first post his resume, and then links to the study. Mix up a big jug of iced tea and get ready to become informed.
No subject in the firearms industry generates more print or heat than terminal performance. In the last fifteen years this issue has even become one of considerable moment with federal agencies, the FBI particularly, leading to the decision to replace entire arsenals of sidearms. Similarly, within the commercial industry we have seen the development of numerous, and occasionally exotic, bullet designs based upon various theories of wounding behavior. Some have worked well, while others have not. But for the most part, shooters and many in the firearms community still do not understand why these things work or fail. My purpose in this study is to examine what we do know and to reconsider the theories which attempt to account for the observed performance. I intend to cover the entire field of terminal ballistics controversy as fairly as possible, but I do have some very definite conclusions of my own which I believe I can explain and defend to the satisfaction of most. Furthermore, I will offer some criticism of the popular formulas for calculating terminal performance and suggest a couple which may provide a real estimate of absolute performance on game (not just a relative comparison to other loads). Although this discussion is intended for the sportsman, I will include material and argument which is of interest to the individual using small arms for self-defense or in police or military applications.
A brief word about my background is warranted. I am a mechanical engineer by profession and employed in the defense industry as an analyst and designer of anti-armor lethal mechanisms (ie, warheads and penetrators). Terminal ballistics is both my hobby and my profession. On the job I use a computational tool known as a "hydrocode" called CTH, which was developed by Sandia National Laboratory, to perform penetration analyses, along with code that I have written for specific applications. My knowledge and studies cover the entire spectrum of penetration mechanics from small arms to high explosive shaped charges. I have extensively read the best forensic studies of bullet behavior, as well as the classic works on field performance by Whelen, Baker, Selous, Taylor, O'Connor, etc. While I freely admit that I haven't personally shot a great number of game animals, I have witnessed others being shot and examined still more post-mortem, to confirm or refute by my own experience the published observations and pontifications of hunters and firearms pundits. I try not to speak dogmatically on subjects beyond my ken, but where the concensus of thought by sage and seasoned scientists and hunters tends toward a clear conclusion, I am not hesitant to assert it.
I believe in being forthright, so I will jump in with both feet and state the premise of my own theory of terminal ballistics. The title of this article is a hint. Plainly stated, I maintain that the effect of bullets upon living targets is caused by the wound track made by the bullet. Now, before you accuse me of being a wise guy, recall that most theoretical explanations of wounding that are batted about in the shooting community are tied to the kinetic energy or momentum or some other such physical quantity of the bullet which is "transferred" or imparted to the target. My theory recognizes these characteristics, but relies upon a fundamentally different premise, which is that two physically equivalent wound tracks in a game animal will have an equivalent effect, no matter how different were the kinetic energies or other physical attributes of the bullets which caused them. There are some extremely rarely encountered exceptions to the general rule, but for most purposes the hole caused by a bullet is its only measure of lethality.
http://www.rathcoombe.net/sci-tech/ballistics/mechanics.html
When you get done with this part, there will be a link to the next. Enjoy!
