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Rifled Weapon Wounds
These show an increased amount of tissue destruction due
to the high velocities involved, and the fact that the projectiles have a large
amount of kinetic energy.
An estimation of firing range is more difficult than
with smooth bore weapons, but in general, contact wounds show similar features
of powder stippling, blackening, burning, tissue disruption and
carboxyhaemoglobin formation.
Due to the high velocity of the bullets, there is
usually an entrance wound and an exit wound, unless the bullet has struck a bony
area such as the skull, and lost it's kinetic energy. The bullet may sometimes
be found just beneath the surface of the skin, and bruise the undersurface
without having the energy to perforate it.
General Features of Entrance Wounds
 | inverted margins |
| abraded margins ('abrasion collar') |
| a dirt ring around the wound caused by the bullet
'cleaning' itself off on the skin as it passes through |
| fibres may be found in the wound from clothing
covering the wound |
| a smaller defect than the diameter of the bullet due
to elastic recoil of the skin |
| skin powder blackening may indicate direction of fire
(eg a circular zone of blackening from a shot fired at right angles to the
skin surface, compared to an oblique zone from an oblique shot etc) |
| stippling/ tatooing of the skin |
| charring of the skin |
| entry wounds caused by shots fired at a distance may
be 'P' or 'D' shaped due to tumbling or 'yawing' of the bullet in its
flight, and there may be surrounding lacerations, allowing the inexperienced
examiner to misinterpret the wound as an exit wound |
| distance entrance wounds are not charred, and there
is no powder deposition or stippling. There is, however, a round entrance
defect and an abrasion collar. |
| Entrance wounds into skull bone typically produces
bevelling, or coning,
of the bone at the surface away from the weapon on the inner table. In thin
areas such as the temple, this may not be observed. Sternum, iliac crest,
scapula, or rib may show similar features. |
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Tangential entrance wounds into bone may produce "keyhole"
defects with entrance and exit side-by-side, so that the arrangement of
bevelling can be used to determine the direction of fire.
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The direction of fire of a graze gunshot wound of the skin surface can be
determined by careful examination of the so- called skin tags located along
the lateral margins of the graze wound trough, by use of a dissecting
microscope or hand lens. Characteristically, the side of the tag
demonstrating a laceration is the side of the projection toward the weapon.
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Use of silencers (or "muzzle brakes" to deflect gas and recoil)
may produce atypical entrance wounds. A silencer is a device, often
homemade, fitting over the muzzle that attempts to reduce noise by baffling
the rapid escape of gases. Entrance wounds
produced when silencers are present lead to muzzle imprints that are
erythematous rather than abraded and disproportionately large for the size
of the wound. Entrance wounds may appear atypical at close range.
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General Features of Exit Wounds
| usually everted and without abrasion collars (unless 'shored' - see below) |
| a larger wound than the entrance wound, due to the
bullet tumbling in it's passage through the body, and bony fragments being
forced out through the skin |
| can be of any size or shape, but are usually
irregular (slit-like, stellate or square) |
| may be similar to the entrance wound in size if the
bullet was fired from a high velocity rifle shot at long distance (eg a
military rifle) |
| a 'shored' exit wound occurs where the wound edges
are abraded against an overlying object pressed firmly against the skin, as
the skin is pushed out from the body by the bullet. Examples of where this
occurs are where the victim was lying on the pavement when shot, or against
a building, ar even where the exit wound passes through the trouser belt.One study showed that such wounds have a greater wound diameter
and demonstrate greater marginal abrasion than control wounds produced by
the same weapons. The features were directly proportional to the KE of the
projectile and the rigidity of the shoring material. |
Issues relating to
distinguishing contact from distant wounds
| where the body is decomposed |
| where the victim survived long enough for healing and
wound repair to take place |
| where multiple layers of clothing have filtered out
soot etc |
| where the edges of a small calibre bullet wound have
dried together |
Location of Wounds
Assessing whether a wound is self-inflicted is assisted
by knowledge of epidemiology. The most common site
for gunshot wound in suicide, for example, is the head (74%), usually the right temple
(39%), followed by chest and abdomen. Men are more likely than women
to shoot themselves in the head.
Entrance / Exit Wounds
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