Theoretical wound ballistics

Question 1

Define wound ballistics

Answer 1

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

Question 2

Define firearms

Answer 2

Also called small arms; are portable guns

Question 3

What are one hand weapons?

Answer 3

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

Question 4

What are two hand weapons?

Answer 4

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

Question 5

What is a caliber?

Answer 5

The diameter of the barrel or bullet

Question 6

Name (typical) calibers for

• short handguns
• rifles
• shotguns

Answer 6

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

Question 7

Name ammunition used by civilans (4)

Answer 7

• 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

Question 8

Name ammunition used by military and police (4)

Answer 8

• 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)

Question 9

Name tissue simulantia

Answer 9

gelatine and soap

Question 10

What are the advantages of gelatine tissue stimulantia?

Answer 10

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

Question 11

What are the disadvantages of gelatine tissue stimulantia?

Answer 11

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

Question 12

what are the advantages of soap tissue stimulantia?

Answer 12

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

Question 13

What are the disadvantages of soap tissue simulantia?

Answer 13

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

Question 14

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

Answer 14

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

Question 15

Characteristics of direct effect

Answer 15

• 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

Question 16

Characteristics of indirect effect

Answer 16

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

Question 17

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

Answer 17

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

Question 18

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

Answer 18

heavy, low velocity, cylinder shape and therefore stable:

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

Question 19

Temporary cavity

Answer 19

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

Question 20

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

Answer 20

heavy, high velocity, pointed and therefore less stable:

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

Question 21

When is tumbling seen?

Answer 21

With military riffle bullets (“Spitzer”)

Question 22

When is fragmentation seen?

Answer 22

With expanding bullets and rifle bullets with a weak jacket construction

Question 23

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

Answer 23

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

• low penetration
• large temporary cavity

Question 24

What is the Hague Declaration and when is it from?

Answer 24

From 1899

Agreement not to use expanding bullets in war

Question 25

Describe the wound profile of a 7.62mm expanding bullet

Answer 25

heavy, high velocity, (expanding) with low penetration

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

Question 26

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

Answer 26

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

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

Question 27

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

Answer 27

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

Question 28

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

Answer 28

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

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

Question 29

Describe the wound profile from shotgun pellets

Answer 29

heavy, low velocity, spherical with high resistance

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

Question 30

Describe the wound profile from a Brenneke bullet (slug)

Answer 30

heavy, low velocity, cylinder shaped, expanding:

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

Question 31

Conclusions

Answer 31

• 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