Understanding Ammunition and Firearm Components

Ammunition

Complete unfired unit for firearms.

Cartridge

Unit containing bullet, primer, and gunpowder.

Paper Cartridge

Early cartridge using a paper tube.

Pin-Fire Cartridge

Brass case with integral firing pin.

Rim Fire Cartridge

Primer in hollow rim of casing.

Center-Fire Cartridge

Primer mounted centrally in cartridge base.

Bullet

Projectile of ammunition, metallic or non-metallic.

Shell

Metallic case holding ammunition components.

Gunpowder

Propellant ignited to move the bullet.

Primer

Igniter that initiates gunpowder combustion.

Dummy Ammunition

Model ammunition, non-firing for display.

Drill Ammunition

Ammunition without gunpowder for training.

Blank Ammunition

Ammunition without a bullet for noise.

Live Ammunition

Functional ammunition designed to fire.

Low Power Cartridge

Muzzle velocity below 1,850 fps.

High Power Cartridge

Muzzle velocity between 1,925 fps and 2,500 fps.

High Intensity Cartridge

Muzzle velocity over 2,500 fps.

Handgun Ammunition

Used in handguns with straight shells.

Rifle Ammunition

Used in rifles with bottle-necked shells.

Shotgun Ammunition

Used in shotguns with wads inside shells.

Boullette

French term meaning small ball, refers to bullet.

Base

Part receiving impact from gunpowder explosion.

Heel

Where heel meets bearing surface on bullet.

Bearing Surface

Peripheral part encountering friction with muzzle.

Core

Mass part of the bullet.

Cannelure

Depression locking bullet to crimp during manufacture.

Shoulder

Meeting point between ogive and bearing surface.

Head Height

Length from bearing surface to bullet point.

Ogive

Curved part extending from shoulder to nose.

Nose/Point

Most anterior part hitting the target.

Meplat

Diameter of the bullet's nose.

Lead Bullet

Bullet made of lead, tin, and steel.

Jacketed Bullet

Bullet covered by copper/nickel strips.

Half-Jacketed Bullet

Bullet partially covered to enhance performance.

Round Nose

Nose shape characterized by a rounded tip.

Pointed Nose

Nose shape with a sharp, pointed tip.

Flat Nose

Nose shape with a flat, blunt tip.

Hollow Point

Nose shape designed to expand upon impact.

Wad

Type of bullet with a wad for sealing.

Semi Wad

Bullet type with partial wad design.

Flat Base

Base shape that is flat.

Round Base

Base shape that is rounded.

Hollow Base

Base shape with a hollowed-out section.

Boat Tail

Base shape tapering towards the rear.

7.62 x 54R

Caliber and length of a specific shell.

+ P

Indicates extra powder in the shell.

Vent/Flash Hole

Hole allowing flame to ignite the propellant.

Armor Piercing

Bullet designed to penetrate armor.

Tracer Bullet

Bullet that illuminates to guide shooter.

Incendiary Bullet

Bullet that explodes due to core explosives.

Fragmentary Bullet

Bullet that dismembers upon striking target.

Soft Point

Hollow point bullet with rubber to limit penetration.

Shell/Casing

Container holding all parts of the ammunition.

Mouth

Opening for bullet insertion during manufacturing.

Crimp

Locks bullet to prevent movement.

Neck

Holds the bullet in place.

Shoulder

Supports the neck of the shell.

Brass case

Tubular metallic part covering the propellant.

Extracting groove

Groove for extractor during shell unloading.

Rim

Prevents shell from moving forward in chamber.

Base

Part of shell located behind the rim.

Shell head

Surface of rim where stamps are located.

Stamp

Indicates brand and caliber of ammunition.

Primer Pocket

Space for inserting the primer at the base.

Caliber

Measurement of bullet diameter, e.g., 9mm.

.45 ACP

.45 Automatic Colt Pistol cartridge.

.22LR

.22 Long Rifle cartridge.

9mm Para

9mm Parabellum, also known as 9x19mm.

Rimmed

Rim diameter larger than shell diameter.

Rimless

Rim diameter equal to shell diameter.

Black powder

Traditional gunpowder composed of nitrate, carbon, sulfur.

Smokeless powder

Modern powder producing minimal smoke when ignited.

Belted type

Shell with a ring above the extracting groove.

Bottle necked

Shell with shoulder, neck smaller than body.

Nitrocellulose

Flammable ingredient in single and double based gunpowder.

Nitroglycerine

Active ingredient in single and double based gunpowder.

Centralite

Burning rate moderator in double based gunpowder.

Vaseline

Ingredient in double based gunpowder for stability.

Inorganic salt

Additional component in double based gunpowder.

Nitroguanidine

Reduces flash and flame temperature in triple based gunpowder.

Cordite

Type of smokeless gunpowder used in ammunition.

Primer

Ignites gunpowder via percussion in ammunition.

Priming cup

Metal container holding sensitive material in primer.

Priming mixture

Sensitive material igniting by percussion in primer.

Disc

Paper covering priming mixture to prevent displacement.

Anvil

Metal part where mixture is crushed to ignite.

Berdan primer

Large primer with anvil attached to shell.

Boxer primer

Smaller primer with anvil inside the cup.

Corrosive priming mixture

Contains potassium chlorate and antimony sulfide.

Non-corrosive priming mixture

Contains barium nitrate and antimony sulfide.

Firearm

Instrument designed to propel bullets using gunpowder.

Antique firearm

Manufactured at least 75 years prior, excluding replicas.

Demilitarized firearm

Made incapable of firing projectiles intentionally.

Forfeited firearm

Subject to court order or considered abandoned.

Imitation firearm

Replica resembling a real firearm closely.

Tampered firearm

Serial number altered to conceal identity.

Class-A Light Weapons

Self-loading firearms under caliber 7.62MM.

Class-B Light Weapons

Crew-operated firearms over caliber 7.62MM.

Long Arms

Firearms fired from the shoulder.

Rifles

Single chamber, rifled barrel, 22 inches minimum.