Is the exploding powder gas of the propellant from blank cartridges sterile?

Wound morphology in contact shots from blank cartridge handguns: a study on composite models

It is a well-known fact that blank cartridge guns can cause penetrating and even fatal injuries when discharged in contact or at very close ranges. In these cases, the gas jet perforates the skin leaving an entrance wound similar to that from a conventional gun. In order to investigate the wound morphology in contact shots from blank firearms, test shots were fired at composite models of pig skin and gelatin blocks using three different calibre 9-mm blank cartridge handguns (two pistols and one revolver) and two types of ammunition. It turned out that the penetrating gas jet produced roundish skin defects resembling bullet entrance holes. Small skin particles from the perforation site were dispersed in the underlying simulant where radiating cracks containing greyish gunshot residues indicated the original expansion of the inrushing combustion gases. Apart from the size of the permanent entrance hole in the skin and the final position of the displaced tissue particles, the penetration depth of the gas jet was determined. Under the specified conditions of the test shots, the zone of mechanical destruction within the simulant was 2.2 to 6.1 cm in length, which illustrates the injuring potential of contact shots inflicted with blank cartridge handguns.

An extraordinary case of an intracranial foreign body after a gunshot to the head

Intermediate targets (IT) can modify the morphology of an entrance wound, the trajectory of the bullet, and contaminate the path with fragments or material from the target. The penetration into the body of big fragments or even of an entire IT is exceptional and only rarely reported in the literature. The interpretation of a gunshot wound after contact of the bullet with IT can sometimes be very tricky as the classical morphology can be missing. The presented case is a rare example of atypical entrance wound and path due to a surprising intermediate target of a gunshot fired against the head.

Gunshot-related transport of micro-organisms from the skin of the entrance region into the bullet path

The skin defect of a gunshot entrance wound is caused by the retrograde and anterograde displacement of skin particles. In the present study, we investigated whether gunshots to bacterially contaminated skin are associated with the transport of micro-organisms into the bullet path. The shots were fired into composite models of pig skin and gelatin blocks. The outer surface of the skin was covered with a thin layer of a defined bacterial suspension [green fluorescent protein-labelled Escherichia coli in the preliminary test and Staphylococcus epidermidis, DSM 1798, in the main test series]. After the bacterially contaminated fluid had dried, test shots were fired from a distance of 5 and 10 m using calibre .38 Special cartridges with different bullet types (round nose, truncated cone, hollow point and flat nose). Subsequent bacteriological analyses showed that all the bullet tracks in the gelatin serving as tissue simulant contained displaced micro-organisms from the skin surface. The results are presented and discussed with reference to the transport of skin particles into the depth of the wound track.

Gunshot injuries as a topic of medicolegal research in the German-speaking countries from the beginning of the 20th century up to the present time

The 100th anniversary of the foundation of the German Society of Legal Medicine is a good opportunity to review its contributions to forensic wound ballistics. The present article gives an overview of the scientific development in this field with special emphasis on work pioneering new developments and findings valid up to the present day, for example the presence of carboxyhemoglobin in the vicinity of the entrance wound as a sign of a contact or close-range shot [A. Paltauf, Wien. Klin. Wochenschr. 3 (1890) 984-991, 1015-1017]; the correct interpretation of the muzzle imprint [A. Werkgartner, Beitr. Gerichtl. Med. 6 (1924) 148-161] and the retrograde ballooning of the bullet entrance region in contact shots [F. Hausbrandt, Dtsch. Z. ges. Gerichtl. Med. 38 (1944) 45-76; H. Elbel, Med. Welt 20 (1958) 343-345]; wound patterns from captive-bolt livestock stunners [H. Czursiedel, Dtsch. Z. ges. Gerichtl. Med. 28 (1937) 132-133]; singeing of synthetic fiber textiles in close-range shots with nitro powder ammunition [S. Berg, Arch. Kriminol. 124 (1959) 5-8,17-22]; the wound ballistic processes on penetration of the bullet and the origin of the abrasion collar [K. Sellier, Beitr. Gerichtl. Med. 25 (1969) 265-270]. More recently medicolegal research in the German-speaking countries covered the following subjects: studies of the dynamic bullet-target interactions in experimental gunshots to simulants and composite body models; use of modern imaging techniques (CT, MRI) in the pre-autopsy diagnosis of lethal gunshot injuries; injuries from blank guns; mechanisms of incapacitation by gunshot injuries; development of improved methods for the evidence of gunshot residues on the firing hand; backspatter from close-range shots; medicolegal contributions in the discrimination of accidental, homicidal and suicidal gunshot injuries.

Lethal head injury due to tear-gas cartridge gunshots

We report a fatal head injury caused by a tear-gas cartridge and point out the underestimated potential injury of this type of weapon. Gas pressure wounds and the death mechanisms are also described. A review of the literature and forensic considerations of head injury without projectile are presented.

Head injury by gunshots from blank cartridges

BACKGROUND

Blank cartridge handguns are generally underestimated in their capacity to inflict serious and potentially life threatening injuries. The predominant reasons for these injuries are suicide or suicide attempts, followed by accidental injuries.

METHODS

A series of 26 gas gunshots to the neurocranium is presented. The injury pattern relevant to neurosurgical practice is illustrated in a case summary of 7 selected cases and the clinical courses as well as outcomes are presented.

RESULTS

The injury pattern demonstrates that the energy density of the gas jet and the high temperatures of the exploding gas volume cause extensive soft tissue injuries. In close-range shots the gas jet takes on physical properties of a projectile. In these injuries impression fractures and dislocation of bone fragments are common.

CONCLUSIONS

Gas handguns, contrary to public opinion, are dangerous weapons and may inflict potentially fatal injuries to the neurocranium when fired at close range. These weapons are frequently used in criminal or careless activities predominantly by young males. Extensive CNS injuries including hematomas, subarachnoid hemorrhage, foreign body contamination, and increased intracranial pressure are frequently observed.

Fatal neck injuries caused by blank cartridges

We report three cases where fatal neck injuries were caused by blanks from starting pistols. The weapons were loaded with blank cartridges or tear gas cartridges. Neither live ammunition nor any form of projectile was used. All three cases involved a contact discharge. The gas pressure caused by firing the weapons created extensive wound cavities in all three cases. Each victim died from blood loss as a result of ruptured cervical vessels; there were no air embolisms. In one case, a man shot himself eight times with two different starting pistols, and the wounds could be matched to each gun by the muzzle imprint marks on the neck.

Fatalities from black powder percussion handguns

Three suicides and one homicide from black powder muzzle loading handguns are reported and the muzzle velocities of two weapons are recorded. The fatal head shots caused wide wound tracts traversing the brains and intracerebral haemorrhages remote from the tract were present in every case. The skulls showed considerable fractures which were pronounced in the cases of contact shots but were also present when the range of fire was 5 m. These extensive injuries from soft lead spheres with muzzle velocities of only approximately 200 m/s are attributed to the expansion of the spheres. The regularly occurring deformation resulted in 13-16 mm calibre missiles in the cases of .44 spheres. The special features of black powder such as incomplete and slow combustion resulted in intense soot deposits in the vicinity of the entrance wound and in long ranges the gunshot residues travelled. In contact shots, large pocket-like underminings even in deeper tissue layers, abundant soot along the trajectory and skin burns were observed.