Forensic Explosives

1. Classification of Gunshot
Wounds
TEJASVI BHATIA

2. Contents
 Introduction
 Nature of gunshot wounds
 Classification
 ENTRANCE WOUNDS
 EXIT WOUNDS
• References

3. INTRODUCTION
Wound ballistics: is a subdivision of terminal
ballistics concerned with the motions and
effects of the projectile in tissue.
Proper evaluation of gunshot wounds
has great importance in:
 Reconstruction of events as to determine
range of fire ,angle of fire and other
useful information.

4. Nature of Gunshot Wounds
 Depress or compress skin, flesh and bone
underneath.
 Pressure stretches them beyond elastic limits.
 Hole formed is smaller than diameter of bullet.
 Bullet crushes and shreds the tissue in its path
forming a temporary cavity.
 Radial displacement of soft tissue forms a
permanent cavity.
 Area of damaged tissue on sides of bullet track
is Zone of extravasation.

5. Contd..
 Zone of extravasation is 12 times and
temporary cavity is 27 times the
permanent cavity.
 Degree of cavitation depends on specific
properties of the tissue involved.

7. Gunshot wounds
Entrance Exit
Contact
Hard Contact
Firm Contact
on Soft surface
Loose Contact
Angled Contact
Incomplete
Contact
Close Range Intermediate
Angled
Distant

9. ENTRANCE WOUND
 Smaller than exit wound.
 Margins are inverted, surrounded by dirt
or grease ring followed by abrasion collar.
 Pink coloration in and around the track
due to carboxy-haemoglobin.
 Blackening, tattooing, muzzle imprint,
singeing of hair ,lead ring ,seared margins
all are indicative of an entrance wound.

11. CONTACT WOUNDS
 Muzzle of weapon is held
against surface of body.
 Cause extensive damage and
“explosive” wounds.
 All the ejecta and the bullet
enters the wound.
 In shotgun, wads are also
present.

12. Hard contact wounds
 Contact is firm, prevents escape of gases, soot
and powder so burning , tattooing, etc. are
minimal or absent.
 Edges are seared and blackened.
 Gases in the track lacerate the deeper tissues
and impart pink coloration.
 Muzzle imprint may or may not be present.
 Cruciform opening with everted margins and
star shape tearing gives an explosive
appearance.

13. Firm contact on soft surface
 Wound may not be eruptive or explosive
type but circular or oval.
 Burning and tattooing may be minimal.
 Margins are inverted but due to coming
out of tissues ,they become everted.
 Clear muzzle imprint, pink coloration and
blackening is present.

14. Loose contact wounds
 Bullet and gas preceding it, indents the
skin ,a temporary gap is formed from
where gas escape with scattering of
muzzle blast.
 This forms an unusual arrangement of
soot. This is called ‘corona’.
 Splitting of margins absent.
 Pink coloration, burning, blackening,
tattooing, muzzle imprint etc occurs.

15. Angled contact wound
 Complete circumference is not in contact
 Eccentrically arranged soot pattern in two
zones occurs i.e. oval, blackened and
seared area and fan shaped zone of light
grey soot.
 Entrance is at base of seared zone and
points the way the gun was directed.
 Powder tattooing is in opposite side of
wound from muzzle.

16. Incomplete contact wound
 Variation of angled contact wounds.
 Area of seared,blackened skin and its
location can be anywhere,where the gap
is present.
 Mostly in self inflicted contact wounds.
 It may be due to momentary break in
contact.

17. CLOSE RANGE WOUNDS
 Muzzle not in contact.
 Zone of blackening is wider.
 Margins ragged,clean with marked destruction of
deeper tissue.
 Entrance circular or oval with everted margins
(rebounding gases),dirt ring , abrasion collar etc.
 Clothing traps most of soot,powder and reduce
flame effect.
 In shotguns,there is no separate pellet holes.

18. Angled close range wounds
 The blackened,
seared area lies on
same side as the
muzzle.
 As the distance
increases, intensity of
blackening and
tattooing decreases
and size of soot or
powder pattern
increases.

19. INTERMEDIATE RANGE
WOUNDS
 Deposition of soot and powder tattooing
are spread over large area.
 No singeing and charring is there.
 Entrance is circular or oval with inverted
margins.
 As range increases tattooing become
sparse and no trace is beyond one yard.

20. Contd…
 In shotgun,beyond 1
yard satellite pellet
holes begin to appear
around main entrance
wound.
 Total diameter of
spread in inches is
roughly equal to
range in yards.

21. DISTANT RANGE WOUNDS
 No charring,blackening,singeing
and tattooing.
 Entrance is circular with inverted
margins,dirt ring,abrasion collar
etc.
 In shotguns,small apertures by
separate pellets appear round the
main wound and on increasing
range,more even distribution of
pellets and disappearance of
central aperture occurs.
 No wad injury.

22. EXIT WOUNDS
 Same general characteristics for all
ranges.
 Larger and more irregular due to
deformation and tumbling of bullet.
 No abrasion ring,dirt ring,powder
tattooing,charring and singeing.
 Shapes may be stellate,slit like, crescent,
circular or completely irregular.
 Some times smaller than entrance.

23. Shored exit wounds
 Broad irregular abrasion band.
 E.g. person shot while leaning against
wall,sitting back in chair etc.
 Everted margins impacting against wall or chair
thus abraded.
 Pattern of overlaying material may get
imprinted.
 Exit from soft tissue-small and slit shaped.
 From hard surface-large, irregular and stellate.

24. Contd…
 Shored exit occur in high velocity, stable,
non fragmented bullet having sufficient
striking energy even after transversing the
body part.
 Also called ‘supported gunshot exit
wounds’.

25.  In shotguns, these are uncommon and
random depending on part involved and
nature of tissue encountered.
 Jagged, irregular laceration, everted
margins with tissue or bone fragments
protruding.

26. References
 DI MAIO.J.M.VINCENT(1987):GUNSHOT WOUNDS ;Practical aspects
of firearms, ballistics and forensic techniques. (pg.53-122)CRC
publications, New York.
 PARIKH.C.K(1990):CBS TEXT BOOK OF MEDICAL JURISPRUDENCE
& TOXICOLOGY(pg.279-301)CBS publishers.
 SHARMA.B.R.(1990): FIREARMS IN CRIMINAL INVESTIGATION &
TRIALS. (Pg. 248-316)UNIVERSAL publications.
 www.gmhafiz.com
 www.srems.com
 www.laslomasscience.com/forensic_ballistics.
 www.firearmstutorials.com
 www.firearmstactical.com