Ballistics Flashcards

1
Q

Explain why ballistic science is important?

A

Firearms were used in:
69% of the US murders
40% of robberies
21.6% of aggravated assaults

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2
Q

Handguns can be held and fired with ______. They are divided into ___ categories. Name them

A
one hand 
3
revolvers 
semiautomatic pistols 
machine pistols
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3
Q
  • Handguns
    Revolvers have a _____ to hold bullets and short _____.
    One pull of the trigger = ___ shot.
    Shell casting remains in the ______ after firing.
A

cylinder cartridges
1
cylinder

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4
Q
  • Handguns
    Semiautomatic pistols have a ____ or a ____.
    Each shot = __ shot.
    empty shells are automatically _____.
A

magazine or clip
1
removed

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5
Q
  • Handguns
    Machine pistols, automatic. It fires ______ (as long as ______).
    ___ similar to semiautomatic pistols.
A

repeatedly
there is ammunition
clip

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6
Q

Rifles often use a ____ or a sliding ___ to eject the spent cartridge. They can be ___ or _____.

A

lever blot

automatic or semiautomatic

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7
Q

Shotguns don’t fire ____, but _____ filled with groups of ___. Those spread out in ____ pattern and the shot spread about an inch for each ___ feet of travel.

A
bullets
shells
pellets
circular
3
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8
Q

Shotguns have no ___ in the barrel, so no ____ marks.

A

grroves

identifying

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9
Q

Intact bullets are ____ found, so bullets often considered _______.

A

rarely

trace evidence

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10
Q

How can we find the manufacturer of the gun?

A

chemical and physical composition of the bullet. powder in the bullets.

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11
Q

What information can be found with a recovered bullet?

A

1- a type of gun
2- trace evidence: paint, fibers
3- DNA flesh and blood.

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12
Q

What are the 3 limits of ballistic science when it comes to recovered bullets?

A

1- severely deformed
2- too small
3- damaged during recovery

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13
Q

____ bullets are soft, deform and fragment as they reach the target and they cause ____ damage.

A

Lead

tissue

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14
Q

Lead ___ bullets are different than Lead bullets because they are mixed with ____ and ____. They deform and fragment (more/less) than lead bullets.
Also, they have (more/less) penetrability.

A

alloy
tin antimony
less
more

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15
Q

Semijacketed bullets have a thin layer of ____ on the side.

They ____ and fragment upon impact.

A

brass

expand

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16
Q

Fully jacketed bullets are ____ covered with brass. They have a ___ penetrating power. They can penetrate body armour which is why they are called ______. Their jacket is made of ___, ____ and other synthetics.

A

completely
greater
cop killer
Teflon, nylon

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17
Q

How do we calculate the calibre of a gun?

How do we calculate the gauge of a gun?

A

1- measurement of the internal diameter of the barrel. in inches or mm
2- number of balls that can fit in the barrel diameter - inverse relation.

18
Q

The shell casing is the part of the bullet that ________.
It retains marks such as:
impression left by the ______ (centre-fire or rim-fire)
_____ pattern
_________
_____ or ejector marks.

A
remains after the powder explodes and the bullet is gone. 
firing pin
breechblock
headstamps
extractor
19
Q

The rifling pattern helps link a ____ to a _____.

A

bullet

gun/gun type

20
Q

Spiral grooves are inside the _____ and make the bullet ____. They make the shot more _____ and create marking that can be used in forensic.

A

barrel
spin
precise

21
Q

depending on the manufaturer:

the____ of the grooves, the _____ of the lands, the direction (______/_______), and the ____ of the twist.

A

depth
width
clockwise/counterclock
degree

22
Q

What are the three things that can link the bullet to a gun (simply with the rifling pattern)?

A

1- lands and grooves
2- twists
3- striations

23
Q

What are the 3 limits of rifling patterns?

A

1- silencer
2- rifling patterns vary from barrel to barrel
3- when using a gun a lot, the grooves and the lands wear down.

24
Q

What are the four steps to individualizing striations?

A

1- obtain intact bullet
2- compare the lab fired bullet + crime scene bullet
3- see if there is a match with a comparison microscope
4- identify or not the perpetrator

25
Q

How many striations (consecutive) are necessary to have a match?

A

3

26
Q

What is a gunshot residue and when is it used?

A

powder that explodes when the shot is fired.

When no gun, no bullets, no shell casing.

27
Q

Where can GSR be found? 8

A
shooters hand 
arm 
clothing 
face
hair
walls
furniture 
victims clothing
28
Q

____ and ____ can change the pattern or lessen the spread of the GSR cloud.

A

wind and rain

29
Q

GSR are visible on ______ clothing, but needs further testing on _____.

A

light-colored

dark

30
Q

Firing distance can be estimated when GSR is found on the ____ of a victim. Only if there was no _____ in between.

A

wound

clothing

31
Q

Firing distance can also be estimated if a pattern of GSR is found on the ______. The farther the distance, the ____ the spread. After a certain distance, ____ residue is found.

A

clothing
wider
no

32
Q

People who get shot rarely die ______. Also, they will probably die of _____ or _____.

A

immediatly
exsanguination
infection

33
Q

The character of the shot depends on: 4

A

1- distance between shooter and victim
2- caliber and velocity f the bullet
3- angle at which the bullet enters the body
4- whether the bullet remains or exits the body

34
Q

When the bullet hits the victim, it creates an ____ wound and sometimes an ____ wound.

A

entry

exit

35
Q

the bullet often (remains in/exits)____ the victim.

determining the entry and exit wound in crucial in _____.

A

remains in

reconstructing the crime scene.

36
Q

Exit wounds are typically ____ because it gets ____ inside the body and ____ its ways out of the tissues.

A

larger
derformed
tears

37
Q

____ bullets are easily deformed and create more damage as the bullet tries to exit the body.

A

softer

38
Q

If the victim wears ___ clothing or is standing ___ a wall, the skin is ___ likely to tear. And the exit wound can look like _____.

A

tight
against
less
an entry wound

39
Q

A shotgun creates ___ entry wounds, creating a ___ pattern which can help determine the ___ between the victim and the shooter.

A

multiple
shot
distance

40
Q

Muzzle 2 feet or more creates:
Muzzle 6 inches to 2 feet creates: because?
muzzle less than 6 inches creates:
muzzle pressed against victim:

A

buising in a halo around the hole
speckles, gunpowder
area charring around the hole
ripping around the whole