Michael Courtney
Member
Contributions to the scientific literature
Here are some abstracts of recently published papers along with links to the full text.
Review of criticisms of ballistic pressure wave experiments, the Strasbourg goat tests, and the Marshall and Sanow data
Authors: Michael Courtney, Amy Courtney
Comments: Related to traumatic brain injury
Subj-class: Medical Physics
This article reviews published criticisms of several ballistic pressure wave experiments authored by Suneson et al., the Marshall and Sanow "one shot stop" data set, and the Strasbourg goat tests. These published criticisms contain numerous logical and rhetorical fallacies, are generally exaggerated, and fail to convincingly support the overly broad conclusions they contain.
link: http://arxiv.org/abs/physics/0701268
Ballistic pressure wave contributions to rapid incapacitation in the Strasbourg goat tests
Authors: Michael Courtney, Amy Courtney
Comments: Related to traumatic brain injury
Subj-class: Medical Physics
This article presents empirical models for the relationship between peak ballistic pressure wave magnitude and incapacitation times in the Strasbourg goat test data. Using a model with the expected limiting behavior at large and small pressure wave magnitudes, the average incapacitation times are highly correlated (R = 0.91) with peak pressure wave magnitude. The cumulative incapacitation probability as a function of time reveals both fast (less than 5 s) and slow (greater than 5 s) incapacitation mechanisms. The fast incapacitation mechanism can be accurately modeled as a function of peak pressure wave magnitude. The slow incapacitation mechanism is presumably due to blood loss via damaged vascular tissue.
link: http://arxiv.org/abs/physics/0701267
Relative incapacitation contributions of pressure wave and wound channel in the Marshall and Sanow data set
Authors: Michael Courtney, Amy Courtney
Comments: Related to traumatic brain injury
Subj-class: Medical Physics
The Marshall and Sanow data set is the largest and most comprehensive data set available quantifying handgun bullet effectiveness in humans. This article presents an empirical model for relative incapacitation probability in humans hit in the thoracic cavity by handgun bullets. The model is constructed by employing the hypothesis that the wound channel and ballistic pressure wave effects each have an associated independent probability of incapacitation. Combining models for these two independent probabilities using the elementary rules of probability and performing a least-squares fit to the Marshall and Sanow data provides an empirical model with only two adjustable parameters for modeling bullet effectiveness with a standard error of 5.6% and a correlation coefficient R = 0.939. This supports the hypothesis that wound channel and pressure wave effects are independent (within the experimental error), and it also allows assignment of the relative contribution of each effect for a given handgun load. This model also gives the expected limiting behavior in the cases of very small and very large variables (wound channel and pressure wave), as well as for incapacitation by rifle and shotgun projectiles.
link: http://arxiv.org/abs/physics/0701266
A method for testing handgun bullets in deer
Authors: Michael Courtney, Amy Courtney
Comments: Related to forensic science and traumatic brain injury
Subj-class: Medical Physics; General Physics
Using service handguns to test bullets in deer is problematic because of velocity loss with range and accuracy giving sub-optimal shot placement. An alternate method is presented using a scoped muzzleloader shooting saboted handgun bullets to allow precise (within 2" in many cases) shot placement for studying terminal ballistics in a living target. Deer are baited to a known range and path obstructions are used to place the deer broadside to the shooter. Muzzleloading powder charges provide a combination of muzzle velocity and velocity loss due to air resistance for a given ballistic coefficient that produce impact velocities corresponding to typical pistol velocities. With readily available sabots, this approach allows for testing of terminal ballistics of .355, .357, .40, .429, .45, and .458 caliber bullets with two muzzleloaders (.45 and .50 caliber). Examples are described demonstrating the usefulness of testing handgun bullets in deer for acoustic shooting event reconstruction, understanding tissue damage effects, and comparing relative incapacitation of different loads.
link: http://arxiv.org/abs/physics/0702107
Michael Courtney, PhD
Here are some abstracts of recently published papers along with links to the full text.
Review of criticisms of ballistic pressure wave experiments, the Strasbourg goat tests, and the Marshall and Sanow data
Authors: Michael Courtney, Amy Courtney
Comments: Related to traumatic brain injury
Subj-class: Medical Physics
This article reviews published criticisms of several ballistic pressure wave experiments authored by Suneson et al., the Marshall and Sanow "one shot stop" data set, and the Strasbourg goat tests. These published criticisms contain numerous logical and rhetorical fallacies, are generally exaggerated, and fail to convincingly support the overly broad conclusions they contain.
link: http://arxiv.org/abs/physics/0701268
Ballistic pressure wave contributions to rapid incapacitation in the Strasbourg goat tests
Authors: Michael Courtney, Amy Courtney
Comments: Related to traumatic brain injury
Subj-class: Medical Physics
This article presents empirical models for the relationship between peak ballistic pressure wave magnitude and incapacitation times in the Strasbourg goat test data. Using a model with the expected limiting behavior at large and small pressure wave magnitudes, the average incapacitation times are highly correlated (R = 0.91) with peak pressure wave magnitude. The cumulative incapacitation probability as a function of time reveals both fast (less than 5 s) and slow (greater than 5 s) incapacitation mechanisms. The fast incapacitation mechanism can be accurately modeled as a function of peak pressure wave magnitude. The slow incapacitation mechanism is presumably due to blood loss via damaged vascular tissue.
link: http://arxiv.org/abs/physics/0701267
Relative incapacitation contributions of pressure wave and wound channel in the Marshall and Sanow data set
Authors: Michael Courtney, Amy Courtney
Comments: Related to traumatic brain injury
Subj-class: Medical Physics
The Marshall and Sanow data set is the largest and most comprehensive data set available quantifying handgun bullet effectiveness in humans. This article presents an empirical model for relative incapacitation probability in humans hit in the thoracic cavity by handgun bullets. The model is constructed by employing the hypothesis that the wound channel and ballistic pressure wave effects each have an associated independent probability of incapacitation. Combining models for these two independent probabilities using the elementary rules of probability and performing a least-squares fit to the Marshall and Sanow data provides an empirical model with only two adjustable parameters for modeling bullet effectiveness with a standard error of 5.6% and a correlation coefficient R = 0.939. This supports the hypothesis that wound channel and pressure wave effects are independent (within the experimental error), and it also allows assignment of the relative contribution of each effect for a given handgun load. This model also gives the expected limiting behavior in the cases of very small and very large variables (wound channel and pressure wave), as well as for incapacitation by rifle and shotgun projectiles.
link: http://arxiv.org/abs/physics/0701266
A method for testing handgun bullets in deer
Authors: Michael Courtney, Amy Courtney
Comments: Related to forensic science and traumatic brain injury
Subj-class: Medical Physics; General Physics
Using service handguns to test bullets in deer is problematic because of velocity loss with range and accuracy giving sub-optimal shot placement. An alternate method is presented using a scoped muzzleloader shooting saboted handgun bullets to allow precise (within 2" in many cases) shot placement for studying terminal ballistics in a living target. Deer are baited to a known range and path obstructions are used to place the deer broadside to the shooter. Muzzleloading powder charges provide a combination of muzzle velocity and velocity loss due to air resistance for a given ballistic coefficient that produce impact velocities corresponding to typical pistol velocities. With readily available sabots, this approach allows for testing of terminal ballistics of .355, .357, .40, .429, .45, and .458 caliber bullets with two muzzleloaders (.45 and .50 caliber). Examples are described demonstrating the usefulness of testing handgun bullets in deer for acoustic shooting event reconstruction, understanding tissue damage effects, and comparing relative incapacitation of different loads.
link: http://arxiv.org/abs/physics/0702107
Michael Courtney, PhD
