Chapter 18: Firearms & Ballistics

Ammunition

Any material fired from a pistol or long un

Automatic firearm

Firearm that continuously fires ammunition as long as the trigger is held

Ballistics

Study of a projectile in flight; includes the launch and behavior of the projectile

Ballistic evidence

Evidence dissociated its the discharge of a projectile from a firearm

Ballistic examiner

Person certified to analyze and provide expert witness testimony on physical ballistic evidence

Breech

End of the barrel nearest to the firing mechanism of a firearm where the cartridge is loaded and unloaded

Breechblock

Metal block located in the back of the firearm barrel that closes the breech at the moment of firing

Breechblock impression

Impression created on the bottom of the cartridge casing as a result of the backward strike of the casing agains the breechblock at the moment of firing

Bullet

Pointed projectile that is released when a firearm is discharged

Caliber

Inside diameter of a firearm barrel and the diameter of its ammunition, as measured in inches or millimeters

Cartridge

Casing that holds a bullet, primer powder, or gunpowder

Firearm

Portable gun that uses a confined propellant to expel a projectile out of a barrel

Firearm examiner

Someone trained to analyze the physical firearm evidence in an investigation

Gauge

Inside diameter of a shotgun barrel and diameter of its amunition

Gunpowder

Explosive mixture that once ignited propel the bullet

Gunshot residue (GSR)

Sot and particles of unturned gunpowder deposited on a person who discharges a firearm; my also be found on close-range victims and adjacent surfaces

Lands

Ridges found on the inside of a firearm’s barrel that are created when the firearm is manufactured

Grooves

depressions or indentions found on the inside of a firearm’s barrel that are created when the firearm is manufactured

Magazine

Cartridge storing device that feeds cartridges into semiautomatic and fully automatic firearms

Muzzle

End of the gun barrel were the projectile is released

National Integrated Ballistic Information Network (NIBIN)

National database of digital images of spent bullet and cartridge case sound at crime scene or test-fired from confiscated weapons

Pistol

Handgun designed to be fired with one hand

Primer

Meta cup that contains the primer powder located in the base of the ammunition

Primer powder

First explosive charge o be ignited in center-fire ammunition

Projectile

Bullet or shot that leaves the barrel of a firearm when propelled by gunpowder explosions

Recoil

Backward movement of a firearm when it is discharged

Revolver

Handgun with a revolving cylinder

Rifle

Long gun that has a barrel with spiral grooves and that is fired from shoulder level

Rifling

Spiral pattern of lands and grooves in the barrel of a firearm

Semiautomatic firearm

Fires a single shot when the trigger is pulled but will reload automatically

Shot

Small round pellets contained within shotgun ammunition

Shotgun

Long gun with a smooth barrel that fires shells filled with shot or a slug

Shotgun shell

Contains shot or a slug, gunpowder and wadding

Slug

Single large projectile used in a shotgun rather than shot pellets

Trajectory

Flight path of a projectile

Wad/wadding

Material that separates gunpowder from the shot/slug in a shotgun shell