Forensic Medicine

2. 2

3.  Any article being capable of projecting
with great force from a fire arm
weapon is known as projectile.
 Pellets in shot guns.
 Bullet in rifled fire arms.
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4.  A bullet is made of lead.
 Since lead is a soft material and easily
deformable, the bullet is jacketed
either fully or partly with cupronickel,
copper.
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5.  Tip of the bullet is known as
the nose.
 A rifle bullet is elongated with
a pointed nose.
 The revolver and pistol bullets
are shorter with a rounded
nose.
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6.  Cartridge case with
percussion cap
containing the
primer at the base.
 Propellant charge
 Projectile
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7.  Bullet: means the
projectile of a rifled
firearm.
◦ a. Dum Dum bullets: are
jacketed bullets with its nose
cut off to expose the core.
◦ They mushroom up in to
pieces when they strike the
body; they are very
destructive and produce
extensive lacerated wounds.
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8.  Tandem bullets/ Piggy back
phenomenon: are bullets
ejected one after other, when
the first bullet, having been
struck in the barrel, fails to
leave the barrel, and is ejected
by the subsequent fired bullet.
When weapon is old or rusty
and faulty.
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9.  Duplex rounds: This
contains two projectiles
by design. They enter
the target at different
points.
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10. ◦ Tumbling bullet: A
bullet that rotates
end –on-end during
its flight is known as
a tumbling bullet.
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11.  JACKETED CONICAL
BULLETS:
Jacketed either fully or
partially with copper,
cupronickel, or other
harder casing. Used in
Rifles.
HARDENED LEAD
BULLETS:
. Made of lead, no
covering. Used in
pistols and revolvers.

12.  TRACER BULLETS:
These bullets have
Barium per oxide
and magnesium
enclosed in their
base.
 These bullets emit
light as they pass,
usually used for
signaling purposes.
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13.  INCENDIARY
BULLETS:
These bullets
contain phosphorus
and burn the
tissues.
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14. BATON CARTRIDGE:
Rubber bullets. 25 –
50 yds.
Now bullets made
of plastic i.e. Teflon
bullets are used.
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15.  Cartridge case with
percussion cap
containing the
primer at the base.
 Propellant charge
 Projectile
 Wad
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16.  Outer shell or covering of the cartridge.
 Generally it is made of brass & shot gun
cartridge is made of cardboard or plastic with
a rimmed brass base.
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17.  The percussion cap at the base contains a
small amount of sensitive detonating
composition known as the primer.
 The primer composition may contains,
◦ Potassium chlorate
◦ Antimony sulphide
◦ lead styphnate,
◦ Barium nitrate
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18.  It is so called because it propels the missile
forwards.
 It is composed of
◦ black powder or
◦ smokeless powder.
 It lies between the primer & projectile.
 Its ignition results in rapid formation of
expanding hot gases under pressure.
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19.  1. BLACK POWDER
 2. SMOKELESS POWDER
 3. SEMI SMOKELESS
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20.  Contains:
 Charcoal 15%,
 Sulphur 10%
 Potassium Nitrate 75%.
 When ignited, it produces a lot of
smoke and some of the powder
is partly burnt or not burnt at all.
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21.  Contain Nitrocellulose alone or with
Nitroglycerine. smokeless powder is burnt
100% .
 It is more effective than black powder as it
burns more efficiently and produces much
less or no smoke.
 Less blackening and tattooing are observed
around the injury.
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22.  85% Black Gun powder.
15% Smokeless Gun powder.
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23.  Above the gun powder
there is a cushion wad.
 Functions;
◦ Separates the projectile from
propellant.
◦ Seals the bore effectively.
◦ Prevents the gases from
escape.
◦ Allows optimum pressure to
be developed.
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24. Fire arm Injuries

26. 1. Gun II. Cartridge Case
a. Pressing a trigger.
b. Detonation of primer c. Ignition of powder
by a firing pin. d. Burning of
powder
e. Production of a
large volume of
gases (within the
closed space of
cartridge.)
f. Increase in
pressure of gases
g. Forces the bullet/pallet out of
cartridge.
h. Through barrel of gun (out of muzzle)

27. a. Discharge of flame.
b. Hot gases.
c Unburned/semi-burnt/burnt powder particles.
d. Grease from barrel of gun.
e. Wad/Jacket

28. Charged
Missile +
Primary Factors
Flame
Gases
Powder
Grease
Wad/Jacket

29.  Abrasion collar or contact ring is present in
which the superficial skin layers are abraded.
It results from the bullet’s initial attempt at
perforating the skin.
 It is also known as contusion collar

30.  This is due to the wipe off the soft metal of
the bullet or dirt present on it, or grease
carried from the barrel and is deposited
round the entrance wound internal to the
abrasion collar.
 The GREASE COLLAR may be absent when
the bullet has passed through clothing.

31.  Gun powder consists of particles which are
embedded under the skin through the force
of their impact.
 It is seen only when the weapon is near
enough for the powder grains to strike with
force.

32.  When the range increases to the point that
the powder particles do not embed
themselves but still leave a visible mark, it is
called stippling.

33.  Wound may cause blood and tissue fragments
to enter the muzzle for several centimeters.
 This appears due to a momentary suction
effect after the pressure of gas blast
subsides, as a result of rapid relative cooling
in the barrel.
 Pieces of skin, hair and adipose tissue have
been found inside the weapon.
 Sometimes the blood and tissue may soil the
hand or arm of person firing the gun.

34. i. Central Hole
ii. Grease Collar -- Grease from barrel– Absent
iii. Collar of abrasion.
iv. Inverted margins
v. Pink coloration
CO + Blood = Carboxy Hemoglobin

35. vi. Charring Flame + Heat ( Tissue burnt completely)
vii. Burning Heat
viii. Blackening Smoke + Burnt powder
ix. Tattooing Unburned + Semi-burnt powder.
x. Singeing Hair shriveled (Flame )

36.  Wound of Entry
 Track
 Wound of Exit
Wound of Entry (Typical):
a. A missile while entering the human body will
i. Hit the skin
ii. Stretch the skin
iii. Effect penetration of skin.
iv. Effect penetration into soft tissue.
v. Effect penetration into the bony tissue.

37.  Rifled weapons may produce two wounds,
◦ one of entry and
◦ one of exit.
The power of penetration is generally
greater with rifled and pistol bullets than with
revolver bullets.