Theoretical wound ballistics Flashcards Preview

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Flashcards in Theoretical wound ballistics Deck (31)
1

Define wound ballistics

The study of the motions and effects of a projectile in tissue

2

Define firearms

Also called small arms; are portable guns

3

What are one hand weapons?

Pistols and revolvers, i.e. short handguns smaller than 30cm

4

What are two hand weapons?

Rifles or shotguns, i.e. long handguns longer than 30cm

5

What is a caliber?

The diameter of the barrel or bullet

6

Name (typical) calibers for

  • short handguns
  • rifles
  • shotguns

  • short handguns: smaller 11,4 mm (0,45 inch)
  • rifles: smaller 12,7 mm (0,5 inch)
  • shotguns: approx 22mm or smaller

7

Name ammunition used by civilans (4)

  • pellets for hunting (shotgun)
  • Brenneke bulltet - illegal single projectiles for shotguns
  • full metal-jacketed lead bullets (for shooting competitions)
  • partial metal-jacketed (expanding) hunting bullets

8

Name ammunition used by military and police (4)

  • full jacketed and partial jacketed pistol and machine gun projectiles (7,65mm and 9mm)
  • full jacketed projectiles for modern rifles (5,56mm)
  • full jacketed projectiles for older rifles (7,62mm; e.g. AK47)
  • full jacketed, armor-piercing projectiles for larger machineguns (12,7mm)

9

Name tissue simulantia

gelatine and soap

10

What are the advantages of gelatine tissue stimulantia?

  • transparent
  • reacts like muscle
  • shows permanent cavity, as it is elastic

11

What are the disadvantages of gelatine tissue stimulantia?

  • difficult to produce
  • quite expensive
  • complicated to measure cavity

12

what are the advantages of soap tissue stimulantia?

  • preserves temporary cavity
  • you buy them ready to use
  • easy to measure cavity

13

What are the disadvantages of soap tissue simulantia?

  • does not correspond to tissue
  • only gives a temporary cavity
  • no see-through - you have to cut it open

14

What are the different effects of the projectile and how are they caused?

  • direct effect: crushing and shearing
  • indirect effect: blast-wave
  • sometimes: indirect effect: sound wave

15

Characteristics of direct effect

  • crushing of tissue is a direct mechanical effect
  • the size of the lesion is connected to the caliber
  • the size of the lesion increases if the projectile is expanding or fragmenting

16

Characteristics of indirect effect

  • lesion in tissue due to overstretching
  • no indirect effect at low velocity of projectile
  • the size of the lesion increases with the velocity

17

What does the permanent cavity correspond to at low and high velocity?

  • low velocity: direct effect of the projectile
  • high velocity: both direct and indirect effect of the profile

18

Describe the wound profile from a .45 full jacked pistol bullet

heavy, low velocity, cylinder shape and therefore stable:

  • high penetration
  • no real temporary cavity
  • the lesion is limited to wound track

19

Temporary cavity

  • only seen at high-velocity lesions when the elasticity of the tissue has been exceeded
  • not relevant when short firearms (only rifles)

20

Describe the wound profile of a 7.62mm NATO military rifle bullet

heavy, high velocity, pointed and therefore less stable:

  • penetration equal to pistol
  • large temporary cavity
  • lesions outside wound track

21

When is tumbling seen?

With military riffle bullets ("Spitzer")

22

When is fragmentation seen?

 With expanding bullets and rifle bullets with a weak jacket construction

23

Describe the wound profile of a 5.56mm NATO military riffle bullet

light, very high velocity, long and pointed and therefore unstable with tendency to fragment

  • low penetration
  • large temporary cavity

24

What is the Hague Declaration and when is it from?

From 1899

Agreement not to use expanding bullets in war

25

Describe the wound profile of a 7.62mm expanding bullet

heavy, high velocity, (expanding) with low penetration

  • large early temporary cavity
  • very large lesion directly under skin

26

Describe the wound profile of a 9mm full jacketed pistol bullet

middle-heavy, middle-velocity, cylinder-shape and therefore stable:

  • large penetration
  • no significant temporary cavity
  • lesion is limited to wound track

27

Describe the wound profile of a 7.62mm AK47 military rifle bullet

Middle-heavy, quite high velocity, pointed but short and therefore quite stable:

  • large penetration
  • temporary cavity deep inside the wound track
  • only large lesions if the wound track is long

28

Describe the wound profile of a 5.45mm AK47 military rifle bullet

 

light, extremely high velocity, long and pointed and therefore unstable:

  • moderate penetration
  • early and large temporary cavity
  • risk for lesions outside the wound track

29

Describe the wound profile from shotgun pellets

heavy, low velocity, spherical with high resistance

  • low penetration
  • no significant temporary cavity
  • extremely large lesion at short range

30

Describe the wound profile from a Brenneke bullet (slug)

heavy, low velocity, cylinder shaped, expanding:

  • moderate penetration
  • no significant temporary cavity
  • only lesion in the wide wound track lesion

31

Conclusions

  • due to the temporary cavity all gunshot wounds are contaminated
  • due to the temporary cavity there could be lesions outside the wound track
  • the specific injury cannot be predicted through knowledge about type of weapon and ammunition, only the potential injury