INTRODUCTION TO FIREARMS-PART 1
This is a guest blog by Digvijay.
We often tend to generalize concepts without understanding them. This blog is meant to get you acquainted with the fundamental terms used in Firearms and its different types that are used by the Indian Armed Forces.
Firearm – A firearm is a portable gun – a barreled weapon that launches one or more projectiles, often driven by the action of an explosive force caused by pressure during the discharge of ammunition.
Terms used in Firearms–
- Ammunition: It is the assembly of a propellant and its projectile in a single package. Propellant is usually a chemical that rapidly burns to create kinetic force. An appropriate amount of propellant is packed with each round of ammunition. In recent years, compressed gas, magnetic energy and electrical energy have also been used as propellants. The Projectile is the part of the ammunition that leaves the weapon and has the effect on the target. This effect is usually either kinetic (Bullets) or through delivery of explosives (Bombs).
- Barrel: A tube, usually metal, through which a controlled explosion or rapid expansion of gases is released to propel a projectile out of the end at high velocity.
- Bayonet: It is a bladed weapon such as a knife or short sword, or spike-shaped weapon designed to fit in, on, over or underneath the muzzle of a rifle, musket or similar weapon. This increases the use of the weapon, as a pike.
- Bipod: A support device that is similar to a tripod or monopod, but with two legs. On firearms, bipods are commonly used on rifles or machine guns to provide a forward rest and reduce motion. The bipod permits the operator to rest the weapon on the ground, a low wall, or other object, reducing operator fatigue and permitting increased accuracy.
- Bolt action: A type of firearm action in which the firearm’s bolt is operated manually by the opening and closing of the barrel with a small handle. As the handle is operated, the bolt is unlocked, the barrel is opened, the spent shell casing is withdrawn and ejected, the firing pin is cocked, and finally a new round/shell (if available) is placed into the barrel and the bolt closed.
- Bullpup: A firearm configuration in which the magazine is located behind the trigger. It has the advantage of reducing the length and weight of the weapon.
- Burst mode: A firing mode enabling the shooter to fire a predetermined number of rounds with a single pull of the trigger. Usually it is two or three rounds in hand held weapons and till the last round in magazine or belt fed weapons.
- Calibre. In arms, it is the internal diameter of a firearm’s barrel usually expressed in millimeters or hundredths of an inch; in measuring rifled barrels this may be measured across the lands (diameter of high points in the rifling) or grooves (diameter of low points in the rifling).
- Carbine: It is a long gun firearm but with a shorter barrel than a rifle or musket. Many carbines are shortened versions of full-length rifles, shooting the same ammunition, while others fire lower-powered ammunition. The smaller size and lighter weight of carbines make them easier to handle. They are typically issued to high-mobility troops such as special-operations soldiers and paratroopers.
- Cartridge: The assembly consisting of a bullet, gunpowder or propellant, shell casing, and primer is called a cartridge. When counting, it is referred to as a “round”. A cartridge without a bullet is called a blank. One that is completely inert (contains no active primer and no propellant) is called a dummy.
- Chamber: The portion of the barrel or firing cylinder in which the cartridge is inserted prior to being fired is the chamber. Rifles and pistols generally have a single chamber in their barrels, while revolvers have six chambers in their cylinders and no chamber in the barrel.
- Holographic weapon sight: A non-magnifying gun sight that allows the user to look through a glass optical window and see a cross hair reticle image superimposed at a distance on the field of view.
- Magazine: It is the ammunition storage and feeding device within or attached to a repeating firearm. Magazines can be removable (detachable) or integral to the firearm. The magazine functions by moving the cartridges stored in the magazine into a position where they may be loaded into the chamber by the action of the firearm. The detachable magazine is often referred to as a clip.
- Muzzle: The part of a firearm at the end of the barrel from which the projectile exits is the muzzle.
- Muzzle velocity: It is the maximum speed of the projectile leaving the muzzle of the gun. It is attained after some distance from the muzzle owing to the continued impact of the rapidly expanding gases. In conventional guns, muzzle velocity is determined by the quality (burn speed, expansion) and quantity of the propellant, the mass of the projectile, and the length of the barrel.
- Rate of fire: The frequency at which an automatic firearm can fire its projectiles is the rate of fire.
- Recoil: The backward momentum of a gun when it is discharged. In technical terms, the recoil caused by the gun exactly balances the forward momentum of the projectile, according to Newton’s third law of motion.
- Rifling: It consists of helical grooves in the internal (bore) surface of a gun’s barrel, which imparts a spin to a projectile around its long axis. This spin serves to improve its aerodynamic stability and accuracy.
- Silencer: Suppressor, sound suppressor, sound moderator, or “hush puppy”: A device attached to or part of the barrel of a firearm to reduce the amount of noise and flash generated by firing the weapon.
- Trigger: A mechanism that actuates the firing sequence of a firearm. Triggers almost universally consist of levers or buttons actuated by the index finger.
- Stock or Butt: The part of a rifle or other firearm, to which the barrel and firing mechanism is attached, that is held against one’s shoulder when firing the gun. The stock provides a means for the shooter to firmly support the device and easily aim it.