Chapter 8: Firearms, Tool Marks, Impressions Flashcards
What are the 3 main types of handguns?
- Single shot pistols
- Revolvers
- Semi automatic pistols
What’s the difference between single shot pistols, revolvers and semi automatic pistols?
- Single-shot pistols fire only one round at a time
- Revolvers feature several firing chambers within a revolving cylinder
- Semi-automatic pistols feature a removable magazine and fire one shot per trigger pull
What are the 2 main type of long guns?
- Shotguns
- Rifles
What ammunition does a shotgun take?
Cylindrical shell ammunition contains numerous ball-shaped projectiles called shot
What’s “rifling”?
Impressing its inner surface with spiral grooves
The diameter of the gun barrel is known as the…?
Caliber
Class or individual? Lands and grooves?
Class
Class or individual? Markings/Striations
Individual
What can you narrow down about a gun using class characteristics?
The type of gun used
In broad terms, whats the process of firing a weapon?
Pulling the trigger releases the weapon’s firing pin, causing it to strike the primer, which in turn ignites the powder.
What type of microscope is used to examine bullets?
The comparison microscope
What is the diameter of a SHOTGUN barrel called?
The gauge
What does NIBIN stand for in terms of ballistics?
National Integrated Ballistics Information Network
How can you determine at what distance was the firearm discharged WITH a suspect weapon.
The distribution of gunpowder particles and other residues around a bullet hole permits an assessment of the distance from which a handgun or rifle was fired.
How can you determine at what distance was the firearm discharged WITHOUT a suspect weapon.
By comparing the test and evidence patterns (tear pattern around the bullet entrance, etc)
