Trauma potential and ballistic parameters of cal. 9 mm P.A. dummy launchers.
BACKGROUND
Blank cartridge actuated dummy launching devices are used by migratory bird hunters to train dogs to retrieve downed birds. The devices create a loud noise while simultaneously propelling a hard foam dummy for retrieval. A newly developed dummy launcher is based on a modified cal. 9 mm P.A. blank handgun with an extension tube pinned and welded to the barrel imitation. Currently, there are no experimental investigations on the ballistic background and trauma potential of these uncommon shooting devices.


METHODS
An experimental test set-up consisting of a photoelectric infrared light barrier was used for measurement of the velocity of hard foam dummies propelled with an automatic dummy launcher. Ballistic parameters of the dummies and an aluminium sleeve as improvised projectile (kinetic energy (E), impulse (p), energy density (E') and threshold velocity (v(tsh)) to cause penetrating wounds as a function of cross-sectional density (S)) were calculated.


RESULTS
The average velocity (v) of the dummies was measured 25.71 m/s exerting an average impulse (p) of 3.342 Ns. The average kinetic energy (E) was calculated 43.04 J with an average energy density (E') of 0.069 J/mm(2). The average velocity (v) of the aluminium sleeves as improvised projectiles was measured 79.58 m/s exerting an average impulse (p) of 2.228 Ns. The average kinetic energy (E) of the aluminium sleeves was calculated as 88.70 J with an average energy density (E') of 0.282 J/mm(2).


CONCLUSIONS
The energy delivered by these shooting devices is high enough to cause relevant injuries. The absence of skin penetration must not mislead the emergency physician or forensic expert into neglecting the potential damage from these devices.
Frank
Matthias
M
Department of Trauma and Orthopedic Surgery, Ernst-Moritz-Arndt-University Greifswald, Germany. matthias.frank@uni-greifswald.de
Bockholdt
Britta
B
Philipp
Klaus-Peter
KP
Ekkernkamp
Axel
A