gunshot wounds - Bloodhounds Incorporated

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FORENSIC PATHOLOGY
GUNSHOT WOUNDS
GUNSHOT WOUNDS

GSW are penetrating or perforating
– Penetrating = bullet enters an object but
does not exit
– Perforating = bullet passes through and
exits object
GUNSHOT WOUNDS

Many things follow the bullet upon
leaving the barrel
– Partially burned powder
– Particles of bullet metal
– Soot
– Bullet lubricant
– Inorganic elements from primer
GUNSHOT WOUNDS

Gunpowder exits the muzzle in two
forms
– Completely burned powder is called soot
or fowling
– Burning and unburned particles are
referred to as stippling or powdered
tattooing

Particles will travel farther than the soot and
will abrade the skin
GUNSHOT WOUNDS

Soot
– Carbon powder which contains vaporized
metals from primer, bullet and cartridge
case
– As range from muzzle to target increases,
size of zone of powder soot blackening
will increase
– Density of blackened soot decreases
GUNSHOT WOUNDS
GUNSHOT WOUNDS

Placement of soot can vary due to
–
–
–
–
–
–
–
Range
Propellant
Angle of muzzle to target
Barrel length
Caliber of weapon
Type of weapon
Target material and state of target (blood or not)
GUNSHOT WOUNDS

Soot
– Barrel length
Longer barrel produces smaller and more
dense soot patterns
 Handguns deposit soot out to 30 cm

– Orientation of muzzle
Muzzle at 90 degree angle = circular shape
with hole in center
 Muzzle at 2cm + angle = blossom shape with
eccentric hole

GUNSHOT WOUNDS
GUNSHOT WOUNDS

Gunshot Wound Residue is deposited
in zones
– Zone I = Contact GSW

Muzzle of weapon held against body surface
– Wound may be classified as hard, loose, angled or
incomplete
– Edges may be seared by gases and blackened by
soot and propellant
 With or without seared blackened zone around
wound
GUNSHOT WOUNDS

Zone I - Hard Contact Wounds
– Muzzle of weapon is jammed “hard” against skin

Outside line of certain parts of the firearm may be
imprinted in the skin
– Barrel, front sights
– Skin is indented by weapon
– Edges of wound are seared by hot gases of
combusted and blackened soot


Soot may be embedded in seared skin
Cannot wash soot out of wound
GUNSHOT WOUNDS
GUNSHOT WOUNDS
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
Zone II – Loose
– approx. 0- 4 inches away from body
– Intense, dark sooting with dense deposits
of unburned and partially burned powder
around bullet hole
– Destruction of clothing and skin possible
GUNSHOT WOUNDS
GUNSHOT WOUNDS

Zone II = Loose Contact
– Muzzle in contact with skin, but held
lightly against surface
– Gas from weapon forms gap between gun
and wound
– Soot is deposited around entrance wound
– Soot can be wiped away
GUNSHOT WOUNDS

Zone II = Angled Contact Wound
– Muzzle is held at an angle to the skin
– Gas and soot radiate outward from muzzle
– Soot is found in two different zones



Most noticeable zone – Blackened seared area of skin
or cloth, having a pear, circular or oval shape
Second zone – large fan-shaped zone of light gray soot
radiating from gap
Soot can be washed away
GUNSHOT WOUNDS

Zone II – Angled Contact Wounds
– Eccentric seared blackened zone of skin
on opposite side of wound from muzzle
pointing the way the gun was directed
– Wound widest on side opposite muzzle
– Larger eccentric zone of soot deposition
GUNSHOT WOUNDS
GUNSHOT WOUNDS

Zone II – Angled Contact Wounds
– If the angle between the barrel and skin
decreases, the gap between muzzle and
skin is larger
More material can escape through the gap
 Unburned grains of powder may sear skin

– Angled contact wounds can have powder
tattooing on opposite side of wound from
muzzle
GUNSHOT WOUNDS
GUNSHOT WOUNDS
GUNSHOT WOUNDS

Zone II – Incomplete Contact Wounds
– Muzzle of weapon is held against the
skin, there is a gap between muzzle and
skin
Soot escapes through gap
 Seared or blackened skin located adjacent to
wound

– Most often seen in suicides
GUNSHOT WOUNDS

Zone III – Near
– Approximately 4 – 6 inches from body
– Medium to light gray sooting
– Circular pattern of powder distribution
around bullet hole
– Tattooing possible
GUNSHOT WOUNDS

Zone IV – Intermediate Range Wounds
– Approximately 6 – 24 inches from body
– No visible sooting
– Dispersed powder particles


As soon as one sees individual tattooing marks, one is
dealing with intermediate range wounds
Near wounds may be seared zone, but no individual
tattoo marks
GUNSHOT WOUNDS

Zone IV – Intermediate
– Tattooing
Reddish-brown to orange-red punctate lesions
around wound entrance
 Skin on same side of barrel (at angle) will
have dense tattooing
 Powder tattooing occurs antemortem

– Postmortem tattooing marks are gray or yellow in
color
GUNSHOT WOUNDS



Zone IV – Intermediate Range Wounds
Powder tattooing is due to impact of
powder grains on skin – Not powder
burns
Punctate abrasions cannot be wiped
away
GUNSHOT WOUNDS


Zone V: Distant Range Wounds
Approximately 2-3 feet or greater
– The only marks on the body are those
produced by mechanical action of bullet
perforating the skin
GUNSHOT WOUNDS
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GUNSHOT WOUNDS
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
Revolvers
– Gas, soot and powder emerge from muzzle and
gap between cylinder and barrel


If weapon is parallel to body soot from cylinder-barrel
gap produces a L- or V-shaped pattern
If weapon is at an acute angel to body, searing will
occur a distance from entrance wound
– Can measure barrel length
GUNSHOT WOUNDS

Muzzle Brake
– Redirects gases at muzzle to generate a forward
thrust on muzzle and counters force of recoil

Flash Suppressor
– Breaks up the “fireball”
– Cylinder with longitudinal slits along its length
– Gases emerges through the slits instead of out
muzzle
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