Firearm Injuries PDF

Firearm injuries  Firearm Weapons Rifled Weapons Non-rifled Weapons Sporting Ghaffir Short Long Guns Guns  Firearm Weapons Rifled Weapons Non-rifled Weapons Rifling and rifling marks: 7 Riflings mean "l...

Firearm injuries  Firearm Weapons Rifled Weapons Non-rifled Weapons Sporting Ghaffir Short Long Guns Guns  Firearm Weapons Rifled Weapons Non-rifled Weapons Rifling and rifling marks: 7 Riflings mean "longitudinal ridges alternating with grooves, running spirally on the inner surface of the barrel parallel to each other". Riflings vary in number, direction (either clockwise or anticlockwise), depth and width. Rifling and rifling marks: 7 Rifling is individual for each weapon; so, no two weapons have the same rifling. 7 Rifling leave on the surface of the fired bullet "rifling marks" which are oblique parallel grooves of the same number, depth, breadth and direction as the riflings. Rifling and rifling marks: ( Functions of Riflings:( to force the bullet from the muzzle in a spiral manner (rotating on its longitudinal axis) to: a)Diminish resistance of air & gravity to the bullet. b)Give it longer range and more power of penetration. c)Increase stability of the bullet. ( Functions of Riflings:( Cartiladges  External wad Shots Internal wad Gun powder Percussion cap µ Cartridge of sporting gun: µ - It's made of a large cardboard or plastic tube with a brass base. µ Cartridge of Ghaftir gun: µ - It's made of a large brass tube with a bonded top. Shots: These are lead pellets are used in non-rifled weapon, which may be machine-made or home-made shots. Shots: These are lead pellets are used in non-rifled weapon, which may be machine-made or home-made shots. Sequence of Gunshots Sequence of events on firing a cartridge: µ Flashes of light (seen before hearing) µ Hot explosive gases Sequence of events on firing a cartridge: µ Smoke and flame: µ UNBURNT POWDER: µ Projectiles or missiles Projectiles or missiles: I- In rifled weapons µ Bullets II- In non-rifled weapons µ Internal wad µ External wad µ Shots Characteristics of Firearm wounds: PBL.7'. F.'/ µ Loss of substance µ Inlet and exit wounds µ Powder marks µ Beveling µ Characters of a typical inlet: :µ Abraded. µ Rounded. µ Its edges are regular and inverted. µ Small. µ Presence of soiling ring at the margins of the wound.  How to differentiate between inlet & Exit Inlet wound Exit wound Loss of substance: More Less Size: Small Large Inverted Everted Edges: Abraded Not abraded Regular Irregular Powder marks: Present in near firing Absent Soiling ring and Present Absent abrasion ring: Colour of tissues or Pink due to carboxy muscles around: haemoglobin in near firing. Co Hb%: up to 60% --- Bevelling of flat bones: Turned in (internal) Turned out (external) Bleeding: Slight Profuse How to differentiate between inlet & Exit Gunshot wound  MLI OF PROJECTILES: - Their presence denotes that the wound is a firearm injury. - They give an idea about type of the weapon used. - They give an idea about distance of firing (diameter of area of dispersion of shots). ( ( What is the MLI OF powder marks:( ( w Wound w Weapon w Direction in tangential firing, the powder marks denote the proximal end of a track; this will be the end nearer to the assailant. w Distance w Differentiation inlet from exit. When? When? When?  Factors affecting the features of inlet Factors affecting the features of inlet: µType of the weapon: Whether rifled (firing bullets) or non rifled (firing shots). µ Density of the tissue: The greater the density of the tissue struck, the greater will be the damage. µDirection of firing: 2 A round inlet will indicate perpendicular hit. 2 An abrasion extending from the margin of wound indicates that the bullet was fired at an angle from the side. The area of abrasion is always nearest to the weapon.  Factors affecting the features of inlet: µSite of the wound: µDistance of firing: The inlet can be classified into three categories: a) Contact b) Near firing. c) Far firing.  Distance of firing (3 types): a) Contact inlet: µ There is usually a thin band of contusion in the margin of wound (muzzle imprints). µ The hair is singed in the contused area. µ The margin of the wound shows burning or even charring by the flame. µ Abrasion ring covered with powder residue. Distance of firing (3 types): Distance of firing (3 types): NEAR INLET: ¥ Near firing inlet is inflicted when the range of firing is less than two meters. It shows all powder marks. FAR INLET: ¥ Such wound results when the range of firing is greater than two meters with absence of all powder marks. Thank You