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Flashcards in Firearms Deck (9)
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1

Firearm accuracy

Generally the accuracy of a firearm can be improved by lengthening it's barrel

2

Rifling

1. Spiral grooves can cause the bullet to spin (improves accuracy)
2. Can be used to identify the weapons manufacturer
3. Imprints different scratch patterns on bullets (striations)

3

Firearm accuracy

Grooves- cut out areas in barrel

Lands- the area between the grooves

Gun manufactures have certain characteristics in rifling (number of lands/grooves, direction of twist, degree of twist

4

Rifling pt 2

•barrel drilling and reaming: a barrel blank is drilled and then smoothed forming the final barrel land surfaces
•broach cutter: a solid rid of steel that is pushed through the barrel of the gun
•drill cuts the grooves and leaves unique marks (striations) from imperfections
•even barrels made in succession won't have identical striations

5

Two main categories of firearms

1. Handguns
•revolver
•pistol
2. Long guns
•rifles
• shotguns

6

Handguns

•compact weapons that can be fired with one hand
• delivers multiple shots without reloading
•shorter barrels to be easily concealed
•barrels have rifling

7

Revolvers

•cartridge cases remain in the cylinder after firing
•fired cartridge cases will be found at a crime scene only if perp reloaded

8

Advantages of Revolvers

1. Cost dependent on brand
2. Simpler
3. More reliable
4. Easier to use
5. Accuracy depends on manufacturing and materials

9

Disadvantages of Revolvers

1. Generally limited to six shots
2. Takes more time to reload
3. Require a more forceful trigger pull
4. Single-action models: hammer must be cocked before each shot