Rifled weapon injuries

Rifled weapon injuries medicolegal importance

1. RIFLED WEAPON INJURIES NUR AINA BINTI AB KADIR

2. CONTENT Classification Parts of firearm Cartridge= case+ detonator + propellant + projectile Rifled firearm injury Entry and exit wound Medicolegal importances

3. CLASSIFICATION

4. CLASSIFICATION

5. PARTS OF FIREARMS

6. CARTRIDGES

7. Case: alloy of copper and zinc Cylindrical One end of the case is closed with a plate of brass  BASE Other end: open Keep the content in place Provides a water proof cover protection R immed revolver Grooved pistol, automatic

8. DETONATOR Primer Ingredients: stored in a small compartment attached to the base of the cartridge case(percussion cap) Location  centre fire and rim fire PROPELLANT(GUN POWDER) Smokeless powder: nitrocellulose alone(single base), combined with niroglycerine (double base)

9. PROJECTILE Bullets Held in the cartridge case by a groove  cannelure Made of lead with a coating of cupro -nickel alloy Conical in shape Tip of bullet nose , different shape Different sizes

10. BARREL Interior of the barrel is scored by a number of parallel, spirally twisted grooves  rifling Bullet is squeezed between the lands  spin/ rotation to the projectile by which it acquires a gyroscopic steadiness prevent wobbling

11. BOLT Block, situated towards the breech end of the barrel Can be opened manually/automatically to insert the cartridge Automatic: magazine- continuous Semi-automatic: 1 cartridge at a time is released Non-automatic: spent cartridge has to be extracted manually

12. ENTRY WOUND Range: distance between the muzzle end of the firearm and the target

13. Abrasion collar: 0.3cm, outer zone Grease collar: 0.7cm, inner zone Contusion collar Burning ( scorching/singeing ) of skin/hair result from flame that emerges from the muzzle,at the time of firing Tattooing (peppering/stippling): grains of gunpowder being driven into the skin Blackening/ smudging : superficial deposit of smoke on the skin Lead ring/metal ring

14. CONTACT SHOT/POINT BLANK Dense area(cranial vault): large,cruciate (cruciform, stellate , star shaped) Thin bone, chest, abdomen: circular, surrounded by abrasion/contusion collar Imprint of the muzzle on the skin Burning, smudging, tattooing are slight/absent Tissue  cherry red colour (carbon monoxide) Surrounding hair: singed

15. CLOSE SHOT Within the range of flame and powder blast , not direct contact with the skin/ cothing Flame travels: 7.5cm(revolver/pistol), 15cm(rifle) Wound: circular hole surrounded by scorching, singeing, smudging (ABSENT=clothing ) Abrasion collar, grease collar, tattooing are present

16. NEAR SHOT Outside the range of flame, within the range of powder blast Wound: circular/oval shape Unburnt powder grains & small metallic particles: - 60cm: revolver,pistol 75cm: rifle Absent: singeing Smudging: 30cm Present: grease and abrasion collar

17. DISTANT SHOT Outside the range of flame and powder blast Wound: circular & inverted margins Scorching, tattooing, smudging: absent Grease and abrasion collar: present

18. EXIT WOUND Larger than entry Absent of scorching, blackening, tattooing, abrasion and grease collar Edges: everted Head: inward bevelling of the skull at the entry, outward bevelling at the exit wound

19. DIFFERENCES CHARACTERISTICS ENTRY WOUND EXIT WOUND SIZE Smaller than diameter of the bullet Larger EDGES Inverted Everted ABRASION&GREASE COLLAR Present Absent BURNING,BLACKENING, TATTOOING May be present Absent BLEEDING Less More FAT EXTRUSION Absent May be present CHERRY RED May be present Absent LEAD RING May be present Absent

20. MEDICOLEGAL ASPECTS OF FIREARM INJURIES Nature of firearm Range of firing Direction of fire Site of firing Cause of death Manner of death

21. QUESTION

22. REFERENCES Textbook of Forensic M edicine and Toxicology,by VV Pillay15 th edition, page 192-209.