Small Arms Terminology

Question 1

Accelerator

Answer 1

A device that operates during the rearward movement of the recoiling parts to increase the speed at which certain parts move. General, when the rate of movement of the bolt or breechblock is increased, the rate of fire is increased.

Question 2

Automatic

Answer 2

A Weapon in which the first round is manually positioned int he chamber, or to be chamber, after the first round is fired, the empty case is ejected and a new round is chambered and fired. This action continues until the trigger is released or the ammunition is expended.

Question 3

Semi-automatic (autoloading)

Answer 3

A weapon in which the first round is manually positioned in the chamber, or to be chambered. After the first round is fired, the casing is extracted and ejected and a new round is chamber, leaving the hammer or firing assembly in the cocked position for the next round. The trigger must be released after each shot and pressure reapplied to fire the next round.

Question 4

Ballistics

Answer 4

The science and study of the motion and impact of projectiles.

Question 5

Three types of ballistics

Answer 5

Internal
External
Terminal

Question 6

Breechblock

Answer 6

A component that seals the breech and blocks the gases from the fired cartridge.

Question 7

Caliber

Answer 7

The distance across the bore of a weapon, measured from land to land expressed in hundredths of an inch. (EX. .30 cal. = thirty hundredths of an inch.)

Question 8

Disconnector

Answer 8

A device incorporated into the action of a weapon which prevents the firing of more than one shot for one pull of the trigger or which prevents the weapon from being fired until the action is fully closed.

Question 9

Headspace

Answer 9

The distance from the breechblock to the part of the chamber which stops the forward movement of the cartridge case.

Question 10

Lands

Answer 10

The raised portion between the grooves in the bore of a gun that impart the spinning motion of the bullet.

Question 11

Rifling

Answer 11

A series of spiral grooves in the bore of a barrel which imparts a spinning motion to the bullet as it travels the length of the barrel from the breech to the muzzle.

Question 12

Sear

Answer 12

A component retained under spring tension that releases, by means of a trigger, either a firing pin, hammer, or bolt.

Question 13

Trigger

Answer 13

A finger actuated lever used to activate the firing mechanism firing the weapon.

Question 14

Choke

Answer 14

Inside bore construction at the muzzle end of the shotguns barrel. Tighter choke equals further max effective range.

Question 15

Internal Ballistics

Answer 15

Science of projectile motion within a firearm. From the time the primer ignites until the bullet leaves the barrel.

Question 16

External Ballistics

Answer 16

Concerns the path of the bullet from the muzzle to the target.

Question 17

Terminal Ballistics

Answer 17

Concerns what happens to the bullet after it hits the target and what the bullet actually does to the target upon impact.

Question 18

Compensator

Answer 18

Device attached to the muzzle of a weapon designed to allow the gases following the bullet out of the muzzle to be deflect upward through slots in the top surface of the compensator. Lower portion of compensator is flat, which allows gas to press against the bottom of the compensator and aids to keep muzzle down.

Question 19

Flash Suppressor

Answer 19

Three or four pronged device attached to the muzzle end of the weapon designed to cool hot gases as it leaves the muzzle behind the round, cooling the gases reduces flash.

Question 20

Muzzle Break

Answer 20

Device attached to the muzzle end of a weapon which deflects the emerging powder gases. Energy imparted by this act of deflection pulls the weapon forward to offset some of the rearward motion of recoil.

Question 21

Breech

Answer 21

Outside rear face of the barrel which meets the face of the bolt or breechblock.

Question 22

Mechanical Safety

Answer 22

An arrangement of components within the action which prevents the weapon from being fired until the action is fully closed and locked.

Question 23

Ejector

Answer 23

A cam or projection inside the receiver against which the cartridge case strikes and is thrown clear of the mechanism after it has been drawn from the chamber by the extractor.

Question 24

Extractor

Answer 24

Cam or projection that engages the rim, or extractor grooves of the cartridge case while the cartridge is in the chamber. After firing the extractor withdraws the case from the chamber when the action is opened.

Question 25

Mechanical Safety

Answer 25

Arrangement of components in the action of a weapon which prevents the weapon from being fired until the action is fully closed and locked.

Question 26

Safety

Answer 26

A mechanism incorporated into the action of a weapon that by mechanical or manual manipulation prevents the weapon from being fired.

Question 27

Trigger Bar

Answer 27

A connecting bar operating between the trigger and the seat. Nothing more than an extension of the trigger.

Question 28

Cartridge

Answer 28

Bullet diameter x cartridge case length. Expressed in millimeters.