Firearms

A little history lesson. Wham! Bam! Thank you, China! Gunpowder first appeared in use in China over a thousand years ago. It was used primarily in firecrackers, but used only sparingly in weapons for military use (cannons). The knowledge of gunpowder manufacturing spread to Europe in the 14th century. The Europeans then realized how much damage a projectile can do to a knight’s armor or a fortification. This led to the development of firearms, and then the use of firearms proliferated rapidly.

Chinese Hand Cannons

Gunpowder (Black Powder) Gunpowder, made of a mixture of sulfur, charcoal, and saltpeter (potassium nitrite: KNO3) The explosive force is due to the result of a little chemistry 1 mole of solid powder  combustion  6 moles of gas This rapid expansion in the enclosed space of a metal tube is used to drive a projectile at high speed in a specified direction. Modern gunpowder is a more refined version of the primitive gun powder . In modern gun powder, the chemical composition has been altered to provide the greatest expansion with the smallest quantity of gun powder and the least amount of residue.

Guns work much like cannons A cannon is just a metal tube. The tube has a closed rear end (breech) and an open front end (bore). The closed end has a small fuse hole (A). Gunpowder (C) is placed in the breech and then cannonball (B) is inserted. The gunpowder and cannonball sit in the breech. A fuse is lit, the flame travels along the fuse and finally reaches the gunpowder. The ignited gunpowder burns rapidly, thus producing a lot of hot gas. The hot gas applies a much greater pressure on the powder side of the cannonball. The cannonball is propelled out of the cannon at high speed.

The Guns Handguns Single shot weapons (target pistol) Revolver Semi-automatic pistol 2. Rifles 3. Shotguns 4. Fully automatic

Manual, Semi-automatic and Automatic In manual guns, the user must insert a round into the chamber, either manually or through the action of the weapon (e.g. levers, pumps, etc), between shots. In semi-automatics, a trigger pull is needed per round fired. For example, to fire ten rounds in a semi-automatic firearm, the trigger would need to be pulled ten times. In contrast, a fully automatic firearm can continue to fire as long as the trigger is held pulled or until it runs out of ammunition.

The 1st handheld guns were essentially mini-cannons: gunpowder, a steel ball & lit a fuse

Need for Speed War typically yields improved weapons technology. In the late 1800’s, the revolver quickly became popular due to its size & quick loading. It only had to be reloaded every 5-6 shots instead of after each shot.

Enter the handgun, not cannon Handguns have reigned supreme for the past 200 years. They remain the most popular and readily available firearm.

Revolvers & Pistols

Basic Anatomy of the Handgun Action Muzzle Chamber Barrel Hammer Magazine (Clip) Bore Caliber Rifling

Just Pull the Trigger Pulling the trigger releases the firing pin… The firing pin strikes the primer… The primer ignites the gun powder… The powder generates gas… The gas propels the bullet forward through the barrel… The spent cartridge case is ejected… The process may be repeated.

Shotguns: Autoloading, Pump & Break

Rifles: Automatic, bolt & lever action

NOMENCLATURE OF THE M16: A Rifle, Not a gun

NOMENCLATURE OF THE M16

How Guns Fire The cartridge goes into chamber Cartridge in chamber Firing pin forcefully strikes primer Primer explodes, ignites powder Gas from burning powder expands in cartridge Gas pushes bullet out with force Speeding bullet exits barrel Bullet and escaping gases make the "BANG”

Ejection!

Components of a Bullet Cartridge Bullet –the projectile that is loaded into a cartridge and fired from a firearm. Only the projectile is fired from the gun Cartridge –This is a self-contained unit that includes an outer casing, projectile (bullet), propellant (gunpowder), and primer (source of ignition). The spent cartridge is ejected from the weapon. Cartridge casing –usually made of brass, steel and aluminum. Better quality cases can be reloaded and reused. Primer – The primer fits into the butt of the cartridge casing or shotgun shell.  It contains an explosive chemical that explodes when a firing pin is slammed into it.  This collision causes the primer to explode and ignite the gunpowder.  Jacket – The metal covering over a bullet that overlies a core of different consistency.  Jackets are used to manipulate the degree of deformation that occurs upon impact.

Bullet Anatomy

Anatomy of a Bullet

More about bullets Bullets come in many shapes and sizes They are made of either soft metals, like lead or hard ones, like bronze. They can be hard if they are solid, or soft, if they have a hollowed tip (hollow-point or hollow-tip). They are either partially or completely covered by a jacket – usually made of copper. (Hence the phrase “Full Metal Jacket”)

Solid Bullets Made of bronze, copper-nickel alloys

Soft-point Bullet a.k.a soft-nose bullet A soft-point bullet, also known as a soft-nosed bullet, is a lead bullet with a copper or brass jacket that is left open at the tip, exposing some of the lead inside.

Hollow-point bullets a.k.a. hollow-nose Contain a hollow in the tip Hollow-tip bullets are designed to “mushroom” upon impact - to cause more tissue damage – used for hunting. They can be partially jacketed (soft-point) or fully jacketed Full metal jacket hollow nose Soft-point hollow nose

Rim-fire vs. Center-fire Cartridges Center-fire cartridges are usually more powerful than rim-fire ones.

Shotgun Shells The projectile of the shotgun shell can either be tiny pellets or “shell” that spray out or a single “slug”. (Wad)

Gauge sizing

Shotgun Shot (pellet) sizing

What is a Caliber? The inside diameter of the barrel of a firearm is called the caliber The word caliber is used to differentiate bullets according to their diameter and the guns by the bullet size they fire. The final number is represented as 1/100th of the actual diameter (inches). A 32 caliber bullet has a diameter of 0.32 inches. It is generally referred to as a “thirty-two caliber". Europeans are metric, so bullet calibers are expressed as mm. For example, a 9mm bullet.

Caliber sizing 9mm soft point bullets

Gradients of Caliber

What is “Magnum”? A cartridge that earns the “magnum” title, has more power or charge than another cartridge of the same caliber.