Guns

Smith & Wesson "Military and Police" revolver.

A gun is a muzzle or breech-loaded projectile-firing weapon. There are various definitions depending on the nation and branch of service. A "gun" may be distinguished from other firearms in being a crew-served weapon such as a howitzer or mortar, as opposed to a small arm like a rifle or pistol, but there are exceptions, such as the U.S. Air Force's GUU5/P. At one time, land-based artillery tubes were called cannon and sea-based naval cannon were called guns. The term "gun" evolved into a generic term for any tube-launched projectile-firing weapon used by sailors, including boarding parties and marines.

In modern parlance, a gun is a projectile weapon using a hollow, tubular barrel with a closed end — the breech — as the means of directing the projectile (as well as other purposes, for example stabilizing the projectile's trajectory, aiming, as an expansion chamber for propellant, etc.), and firing in a generally flat trajectory.

The term "gun" has also taken on a more generic meaning, by which it has come to refer to any one of a number of trigger-initiated, hand-held, and hand-directed implements, especially with an extending bore, which thereby resemble the class of weapon in either form or concept. Examples of this usage include staple gun, nail gun, glue gun, grease gun. Occasionally, this tendency is ironically reversed, such as the case of the American M3 submachine gun which carries the nickname "Grease Gun".

Most guns are described by the type of barrel used, the means of firing, the purpose of the weapon, the caliber, or the commonly accepted name for a particular variation.

Barrel types include rifled—a series of spiraled grooves or angles within the barrel—when the projectile requires an induced spin to stabilize it and smoothbore when the projectile is stabilized by other means or rifling is undesired or unnecessary. Typically, interior barrel diameter and the associated projectile size is a means to identify gun variations. Barrel diameter is reported in several ways. The more conventional measure is reporting the interior diameter of the barrel in decimal fractions of the inch or in millimeters. Some guns—such as shotguns—report the weapon's gauge or—as in some British ordnance—the weight of the weapon's usual projectile.

A gun projectile may be a simple, single-piece item like a bullet, a casing containing a payload like a shotshell or explosive shell, or complex projectile like a sub-caliber projectile and sabot. The propellant may be air, an explosive solid, or an explosive liquid. Some variations like the Gyrojet and certain other types combine the projectile and propellant into a single item.


Terminology

The use of the term "cannon" is interchangeable with "gun" as words borrowed from the French language during the early 15th century, from Old French canon, itself a borrowing from the Italian cannone, a "large tube" augmentative of Latin canna "reed or cane". Recent scholarship indicates that the term "gun" may have its origins in the Norse woman's name "Gunnildr" (or "Gunnild", possibly Queen Gunhild of Wenden, wife of King Sweyn Forkbeard[citation needed]), which was often shortened to "Gunna".The earliest recorded use of the term "gonne" was in a Latin document circa 1339.

Other names for guns during this era were "schioppi" (Italian translation-"thunderers"), and "donrebusse" (Dutch translation-"thunder gun") which was incorporated into the English language as "blunderbuss". Artillerymen were often referred to as "gonners" and "artillers". Early guns and the men who used them were often associated with the devil and the gunner's craft was considered a black art, a point reinforced by the smell of sulfur on battlefields created from the firing of guns along with the muzzle blast and accompanying flash.

In military use, the term "gun" refers primarily to direct fire weapons that capitalize on their velocity for penetration or range. In modern parlance, these weapons are breech-loaded and built primarily for long range fire with a low or almost flat ballistic arc. A variation is the howitzer or gun-howitzer designed to offer the ability to fire both low or high-angle ballistic arcs. In this use, example guns include naval guns. A less strict application of the word is to identify one artillery weapon system or non-machine gun projectile armament on aircraft.

The word cannon is retained in some cases for the actual gun tube but not the weapon system. The title gunner is applied to the member of the team charged with operating, aiming, and firing a gun.
Autocannon are automatic guns designed primarily to fire shells and are mounted on a vehicle or other mount. Machine guns are similar, but usually designed to fire simple projectiles. In some calibers and some usages, these two definitions overlap.

A related military use of the word is in describing gun-type fission weapon. In this instance, the "gun" is part of a nuclear weapon and contains an explosively propelled sub-critical slug of fissile material within a barrel to be fired into a second sub-critical mass in order to initiate the fission reaction. Potentially confused with this usage are small nuclear devices capable of being fired by artillery or recoilless rifle.
In civilian use, a related item used in agriculture is a captive bolt gun. Such captive piston guns are often used to humanely stun farm animals for slaughter.

Shotguns are normally civilian weapons used primarily for hunting. These weapons are typically smooth bored and fire a shell containing small lead or steel balls. Variations use rifled barrels or fire other projectiles including solid lead slugs, a Taser XREP projectile capable of stunning a target, or other payloads. In military versions, these weapons are often used to burst door hinges or locks in addition to antipersonnel uses.

Types of guns

Military firearms

Long gun

• Arquebus
• Blunderbuss
• Musket
• Musketoon
• Wall gun
• Grenade launcher
• Submachine gun
• Personal defense weapon
• Rifle
• Lever action rifle
• Bolt action rifle
• Assault rifle
• Battle rifle
• Carbine
• Service rifle
• Sniper rifle
• Shotgun
• Combat shotgun
• Semi-automatic shotgun
• Automatic shotgun
• Flamethrower

Machine guns

• Gatling gun
• Minigun
• Nordenfelt gun
• Metal storm
• Mitrailleuse
• Submachine gun
• Machine pistol

• Machine gun
• General-purpose machine gun
• Light machine gun
• Squad automatic weapon
• Infantry Automatic Rifle
• Medium machine gun
• Heavy machine gun

Handguns

• Handgun
• Service pistol

• Revolver
• Service revolver

• Machine pistol

Autocannon

• Autocannon
• Chain gun
• Revolver cannon

Artillery guns

• Artillery gun
• Cannon
• Carronade
• Falconet
• Field gun
• Howitzer

Tank guns

• Tank gun

Hunting guns

• Elephant gun
• Express rifle
• Shotgun
• Muzzleloader
• Breechloader

Guns for training and entertainment

• Air gun
• Airsoft gun
• BB gun
• Drill Purpose Rifle
• Paintball gun
• Replica gun
• Inert gun
• Spud gun
• Water gun
• Nerf gun

IOF .32 Revolver chambered in .32 S&W Long

Mamba Pistol 9x19mm Parabellum automatic pistol

Lee-Enfield Jungle Carbine chambered in .303 British

TKB-059 assault rifle chambered in 7.62x39mm

Operating principle

Generally, guns use compressed gas confined by the barrel to propel the bullet up to high speed, though devices operating in other ways are sometimes called guns. In guns that are firearms the high pressure gas is generated by combustion, usually of gun powder. This principle is similar to that of internal combustion engines, except that the bullet leaves the barrel, but the piston transfers its motion to other parts and returns down the cylinder. 

As in an internal combustion engine, the combustion propagates by deflagration rather than by detonation, and good gunpowder, like good motor fuel, is resistant to detonation. This is because much of the energy generated in detonation is in the form of a shock wave, which can propagate from the gas to the solid structure and heat or damage the structure, rather than staying as heat to propel the piston or bullet. The speed of a shock wave at such high temperature and pressure is much faster than that of any bullet.

History of the firearm

Firearms were invented in the 12th century in China, after the Chinese had invented gunpowder in the 9th century. These inventions were later transmitted to the Middle East and to Europe.

The phalanx-charging fire-gourd, 

one of many fire lance types 

discharging lead pellets

 in the gunpowder blast, 

an illustration from the

 Huolongjing, 14th century.

Firearms in China

The direct ancestor of the firearm is the fire-lance, a gunpowder-filled tube attached to the end of a spear and used as a flamethrower; shrapnel was sometimes placed in the barrel so that it would fly out together with the flames. The earliest depiction of a gunpowder weapon is the illustration of a fire-lance on a mid-10th century silk banner from Dunhuang. The Tê-An Shou Chhêng Lu, an account of the siege of De'an in 1132, records that Song forces used fire-lances against the Jurchens.

In due course, the proportion of saltpeter in the propellant was increased to maximise its explosive power. To better withstand that explosive power, the paper and bamboo of which fire-lance barrels were originally made came to be replaced by metal.And to take full advantage of that power, the shrapnel came to be replaced by projectiles whose size and shape filled the barrel more closely. With this, we have the three basic features of the gun: a barrel made of metal, high-nitrate gunpowder, and a projectile which totally occludes the muzzle so that the powder charge exerts its full potential in propellant effect.

The earliest depiction of a gun is a sculpture from a cave in Sichuan dating to the 12th century of a figure carrying a vase-shaped bombard with flames and a cannonball coming out of it. The oldest surviving gun, made of bronze, has been dated to 1288 because it was discovered at a site in modern-day Acheng District where the Yuan Shi records that battles were fought at that time; Li Ting, a military commander of Jurchen descent, led foot-soldiers armed with guns—including a Korean brigade—in battle to suppress the rebellion of the Christian Mongol prince Nayan.

Hand cannon from the Chinese Yuan Dynasty (1271-1368).

Firearms in Southeast Asia

The first record of firearms in Vietnam Đại Việt is the death of the Champa king Chế Bồng Nga in 1390 killed by a volley of Huochong.

Firearms in the Middle East

The Arabs obtained firearms in the 14th century. Al-Hassan claims that the Battle of Ain Jalut in 1260 saw the Mamluks use against the Mongols in "the first cannon in history" gunpowder formulae which were almost identical with the ideal composition for explosive gunpowder. However, Khan states that it was invading Mongols who introduced gunpowder to the Islamic world and cites Mamluk antagonism towards early riflemen in their infantry as an example of how gunpowder weapons were not always met with open acceptance in the Middle East.

Firearms in the West

One theory of how gunpowder came to Europe is that it made its way along the Silk Road through the Middle East; another is that it was brought to Europe during the Mongol invasion in the first half of the 13th century. English Privy Wardrobe accounts list "ribaldis," a type of cannon, in the 1340s, and siege guns were used by the English at Calais in 1346.

The first mention of firearms in Russia is found in the "Sofiiskii vremennik" chronicle, where it is stated that during the 1382 defense of Moscow from Tokhtamysh's Golden Horde, Muscovites used firearms called "tiufiaks" (Russian: "тюфяки", which were of Eastern origin; this word derives from Turkic "tüfeng", meaning "gun").

The earliest surviving firearm in Europe has been found from Otepää, Estonia and it dates to at least 1396.

Around the late 14th century in Europe, smaller and portable hand-held cannons were developed, creating in effect the first smooth-bore personal firearm. In the late 15th century the Ottoman empire used firearms as part of its regular infantry.

Guns - Safavid Empire - Iran (Persia)

Early modern age

During the Early modern age, these hand-held cannons evolved into the flintlock rifle, then the breech loader and finally the automatic weapon.

Early firearms had to be cocked and caught by the "sear", which holds the hammer back, before each shot. Pulling the trigger allows the hammer or striker to fly forward, striking the "firing pin," which then strikes the "primer," igniting an impact-sensitive chemical compound (historically, first fulminate of mercury, then potassium chlorate, now lead styphnate) which shoots a flame through the "flash hole" into the cartridge's propellant chamber, igniting the propellant.

As ignition devices, matchlocks, wheellocks, snaplock, flintlocks and percussion locks were used in turn.

The paper cartridge was introduced in 1586, and the bayonet came to use in 17th century France. Hand grenades, thrown by grenadiers, appeared around the same time.

Page showing a musketeer (Plate 4) from Jacob van Gheyn's 

Wapenhandelingen van Roers, Musquetten ende Spiesen (1608)

The Springfield Armory in Springfield, Massachusetts became important to the history of firearms during the 1850s, when it debuted the Springfield rifle. Springfield rifles were among the very first breech-loading rifles, starting production in 1865. By that time, metallurgy had developed sufficiently so that brass could be worked into fixed ammunition. 

Previously, each round was custom made as needed: the shooter poured loose powder down the barrel, used leather or cloth for wadding if time allowed, selected a suitable projectile (lead ball, rocks, arrow, or nail), then seated the projectile on top of the powder charge by means of a ramrod. Performance was erratic. Fixed ammunition combined a primer, the pre-measured charge, and the projectile in a water-resistant brass cartridge case. Most importantly, the soft brass expanded under pressure of the gas to seal the rear end of the barrel, which prevented the shooter from being maimed by escaping high-pressure gases when he pulled the trigger.

Repeating and automatic firearms

A repeating firearm or "repeater" is a firearm that holds more than one cartridge and can be fired more than once between chargings. The most well-known repeater is the American, Springfield Model 1892-99 -- also made at the Springfield Armory in Springfield, Massachusetts -- which were used during the Spanish-American War.

 Some repeating firearms require manipulation of a bolt, (as in bolt action), lever, or slide to eject the fired cartridge case, draw a fresh cartridge from the magazine, and insert it into the firing chamber, and "cock" (draw to the rear and place under spring tension) the hammer or striker, so that pulling the trigger will fire the weapon. 

Others use either the firearm's recoil, or a small portion of the propellant gas drawn from the barrel, to operate the firearm's mechanism and ready it for the next shot. Such firearms are sometimes called "self-loading," but are more commonly known as semi-automatic, if they fire one shot for every pull of the trigger, or automatic or "full-auto" if they continue to fire until the trigger is released or the magazine is empty.

 A revolver is a unique type of firearm in which a rotating cylinder holds a number of cartridges; the cylinder "revolves" to align each "chamber" or "charge hole" with the rear of the barrel, hold the cartridge and contain the pressure (up to 65,000 pounds per square inch or 450 MPa) produced when the cartridge is fired. Thus the cylinder serves as both magazine and firing chambers. 

There are also "single- shot" and multiple-barrel firearms, which hold only one cartridge per barrel and must be reloaded manually between shots.

The earliest repeating firearms were revolvers (revolving rifles were sometimes called "turret guns") and were "single action" in that they could only be fired one way: by manually cocking the mechanism (drawing the hammer to the rear with the thumb) before each shot. This design dates from 1836, with the introduction of the Colt Paterson, or even earlier. Though they are slower to reload and fire than some other types of firearms, single-action revolvers are of a simple, strong design, and are still made, though they are nowadays used more often for hunting than for self-defense. The double-action revolver is a design almost as old as the single action. A double-action revolver can be fired in either of two ways. 

One can cock the hammer (the action of which moves levers to rotate the cylinder and align a fresh cartridge with the rear of the barrel), then pull the trigger for each shot ("single-action mode") or one may simply pull the trigger, through a longer, heavier stroke. This causes levers and springs to both rotate the cylinder and draw the hammer to the rear, then release it, firing the cartridge. Firing a double-action revolver in single-action mode tends to be more accurate, because the trigger pull is much shorter and lighter; usually four or five pounds-force (18−22 newtons) of pull is sufficient, instead of the twelve to twenty pounds (50−90 N) required for double-action mode, so the firearm's aim is less likely to be disturbed by the force of pulling the trigger.

Self-loaders are firearms that use some of the discharge energy to reload the firearm. These are also called semi-automatics. These are typically fed from a tube or detachable magazine, commonly but incorrectly referred to as a “clip” (which correctly denotes a magazine reloading device used in certain rifles, or a retainer for flangeless bullets used in certain revolvers). The most well-known, American, semi-automatic rifle is the M-1 Garand, developed in 1919 at the Springfield Armory in Springfield, Massachusetts. After years of research and testing, the first production model of the M1 Garand was unveiled in 1937. During World War II, the M1 Garand gave American infantrymen an advantage over their opponents, most of whom were issued slower firing bolt-action rifles.

Automatics (also called full autos, machine guns, or machine pistols) were not practical until the development of smokeless powder in the late 19th century. Black powder caused too much fouling of the mechanism to allow automatics or self-loaders to be reliable. The Springfield-developed M14 rifle, considered the last "battle rifle," is an automatic. The M14 used by Americans soldiers during the Korean War and the Vietnam War.