Examination of Firearms Review: 2007 to 2010 - Interpol

measured the ballistic parameters of the 9 x 17 mm cartridge that is commonly
used for such devices (106).
In two different articles, Ogunc et al. (107) and Saribey et al. (108) examine the
wounding potential of modified blank ammunition. Blank weapons are fairly
accessible (Blank pistols costing only 10% of "real" guns can be purchased by
over 18-year olds without any license) in Turkey and were seized in great
numbers in modified condition. The authors discuss the modification process:
either replacement of the original obstructed barrel with a smooth one, in which
cases the firing of live ammunition becomes possible or the removal of the
obstruction (restraint piece) in which case only modified blank ammunition can be
discharged. In the latter case, the ammunition is adapted as follows: removal of
plastic wad and replacement with a lead or steal sphere (shotgun pellets or ball
bearings). The wounding potential was examined using ballistic gelatine and
ballistic candle blocks, coated with a skin stimulant and different clothing
simulants. In all cases, penetration occurs, it being deeper for the steel (mean:
8.608 cm) than for the lead spheres (mean: 6.434 cm) (bare skin situations). It
can be expected that fatal injuries can occur if such firearms are discharged from
a close distance. These modified blank guns are more and more being
encountered in criminal activities.
As for wound ballistic testing, gelatine is a long established and reliable tissue
simulant. The projectile penetrating the gelatine transfers energy and causes
radial cracks according to the temporary cavity. Gelatine can be an ideal way to
study the behaviour of air rifle pellets, as was done by Wightman and his
colleagues (109). They have investigated the influence of quite a few parameters
on the behaviour of the pellets: comparing 1/ different gels, 2/ different gel
concentrations, 3/ different delivery powers, 4/ pellet shape, 5/ firing range. They
have furthermore examined the effect of bone: damage to the bone was not
observed but the pellets suffer important deformation. Computed tomography
allows examination of bone and pellet damage in situ in 3D. In ballistics gelatine,
the crack length is a function of the energy spent. Schyma used colour contrast
(acryl paint) to render the fissures more visible (110). It was concluded that doing
so, the measurements were more reproducible and the curve of the wound
profile typically shifts by 1 cm to the entry.
Frank et al. examined the trauma potential and ballistic parameters of cal. 9 mm
P.A. dummy launchers (111). These are typically used for dog training: a hard
foam dummy is launched for the dog to retrieve. It was concluded that for two
projectiles (1/ the complete foam dummy and 2/ the aluminium mounting sleeve
separately), the energy densities were 0.069 J/mm² and 0.282 J/mm² and thus
high enough to cause relevant injuries.
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