Ballistics and Firearms Science

This set of vocabulary flashcards covers the fundamental concepts of ballistics, firearm classification, cartridge components, forensic identification markings, and bullet trajectory based on the lecture contents.

Ballistics

The study of bullets and firearms.

Firearm

A weapon capable of firing a projectile using a confined explosive.

Hand Gun

A classification of modern firearms including pistols and revolvers that can be fired with one hand.

Long Gun

A classification of modern firearms including rifles and shotguns that require two hands to operate.

Semi-automatic

A firearm that fires one bullet per pull of the trigger.

Fully automatic

A firearm that fires repeatedly as long as the trigger is pressed.

Rifle

A type of long gun that fires bullets.

Shotgun

A type of long gun that fires pellets (multiple projectiles) or a slug (single projectile).

Cartridge

A unit composed of a bullet, casing, gunpowder, rim, and primer.

Bullet

The projectile part of a cartridge that is pushed from the casing and into the barrel.

Casing

The part of the cartridge that contains the gunpowder and is sent backward against the breechblock during firing.

Gunpowder

The explosive material inside a bullet cartridge that is ignited by the firing pin hitting the primer.

Primer

The part of the cartridge base that is hit by the firing pin to ignite the gunpowder.

Firearm Identification

A method used in forensics to determine if a particular bullet or cartridge was shot from a particular weapon based on unique, reproducible markings.

Striations

Scratch marks left on a projectile by the rifling lines of the inside of the barrel.

Lands and Grooves

Unique patterns within a barrel that produce unique markings and make a projectile spin around its long axis when fired.

Breech Markings

Unique marks produced as the cartridge casing moves back and strikes the breechblock during the recoil process.

Breechblock

The mechanism in a firearm that prevents the cartridge from shooting toward the user as it recoils.

Newton's 3rd Law

The physics law explaining why the explosive force that pushes a bullet forward also sends the casing backward against the breechblock.

Firing Pin Markings

A unique stamping left on the cartridge’s primer or rim by the firing pin of a firearm.

Gunshot Residue (GSR)

Traces of smoke and particles of unburned powder carried from the firearm by expanding gases that can stick to the person holding the firearm.

Trajectory

The path or flight path of a projectile, which can be calculated by finding two reference points such as bullet holes or wounds.

RICHOCHETE

The result of a bullet that hits a hard surface.