Gunshots Flashcards
What do smooth bore weapons fire?
Multiple pellets e.g. shotgun
What kind of weapojn is a handgun?
Rifled
Give examples of interior ballistics?
- Rifling karks on bullet: class characteristics for make/model, individual for unique to gun
- Cartridge case
- Primer cap/firing pin
- Fingerprints
What makes up primer in small arms?
Lead. barium and antimony
What types of primer are there?
Centre fire and rim fgire
What makes up propellant
Smokeless poweder:: nitrocellulose plus/mins nitroglycerine
When are lead bullets used?
In revolvers and 22 rimfire cartridgres
What kind of lead bullets are available?
Round nose#Wadcutter and hollow point
What are jacketed bullets used in?
Autoloading pistols and HV rifles
What kind of types of jacketed bullets exist?
Full metal jacket (HV military rifle)
Partial metal jacket (hunting and autoload pistol)
Semi-jacketed hollow soft point (hunting)
Silvertip (al)
What kind of wound do bullets cause?
Direct laceration
Explain temporary cavity?
lasts 800 m/s
Wide zone of haemorrhage around permanent cavity
Dense inelastic organ (liver) may rupture
With a pistol: how far out does the flame go?
3 inches
With a pistol: how far out does the smoke go?
6 inches
With a pistol: how far out does the tattooing go?
18 inches
When bullet enters and exits what is hole size like?
Small on entry, big on exit
What size are temporary cavities?
30-40 times that of bullet, tremendous pressure and lasts milliseconds
What causes tattooing?
Propellant
At contact range, what is seared into margins?
Soot and propellant
Between contact and intermediate range what occurs?
No tattooing, soot and propellant seared into margins and peripheral ring of soot staining (soot reaches 20-30cm and can be wiped off)1
Whast is intermediate range?
Few cm to 1m (within arms readch)
What do yoy get at intermediate range?
Powder tattooing: unburt propellany, individual reddish brown punctate abrasions, rim of bruising (vital reaction ), eccentric pattern if angled entry, raches up to 30-45 cm
What is distant range?
Beyond arms length so beyond 1m
What do you see at distant range?
No propellant, flame or soot, bullet is on its own, skin defect with marginal abrasion
Compare entry vs exit: shape of defect?
Entry: circular
Exit: irregular
Compare entry vs exit: diamter?
Entry: less than bullet
Exit: wider than bullet
Compare entry vs exit: abrasions?
Entry: abraded margin
Exit: no abrasion (shored)
Where are gunshot residues deposited
On radial side of firing hand
