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A gun is a device designed to discharge a projectile. The
projectile may be solid, liquid, gas or energy and may be free, as with
bullets and artillery shells, or captive as with Taser probes and whaling harpoons.
The means of projection varies according to design but is usually
effected by the action of gas pressure, either produced through the
rapid combustion of a propellant
or compressed and stored by mechanical means, operating on the
projectile inside an open-ended tube in the fashion of a piston. The
confined gas accelerates the movable projectile down the length of the
tube imparting sufficient velocity to sustain the projectile's travel
once the action of the gas ceases at the end of the tube or muzzle.
Alternatively, acceleration via electromagnetic field generation may be
employed in which case the tube may be dispensed with and a guide rail
substituted.
In ordinary speech the term gun may refer to any sort of firearm including those that are usually hand-held (handgun).
The word gun is also commonly used to describe objects which, while
they are not themselves weapons, produce an effect or possess a form
which is in some way evocative of a handgun or longarm.
However, in contemporary military and naval parlance the term gun has a
very specific meaning and refers solely to any large-calibre,
direct-fire, high-velocity, flat-trajectory artillery piece employing an
explosive-filled hollowed metal shell or solid bolt
as its primary projectile. This later usage contrasts with
large-calibre, high-angle, low-velocity, indirect-fire weapons such as howitzers, mortars, and grenade launchers which invariantly employ explosive-filled shells.
The origin of the English word gun is presently considered to derive from the name given to a particular historical weapon. Domina Gunilda was the name given to a remarkably large ballista, a mechanical bolt throwing weapon of enormous size, mounted at Windsor Castle during the 14C. This name in turn may have derived from the Old Norse woman's proper name Gunnhildr which combines two Norse words referring to battle. In any case the term gonne or gunne was applied to early hand-held firearms by the late 14C. or early 15C.
Modern guns are typically described by their bore diameter (75mm) or calibre
(7.62mm), the type of action employed (muzzle, breech, lever, bolt,
revolver, semi-automatic, or automatic) together with the usual means of
deportment (hand-held or mechanical mounting). They may be further
distinguished by reference to the type of barrel used (rifled), the
barrel length (19 inch) or calibre (L55), the design's primary intended target (anti-aircraft), or the commonly accepted name for a particular variation (Gatling gun).
Barrel types include rifled—a series of spiralled 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. Bore
diameter is reported in several ways. The more conventional measure is
reporting the interior diameter (bore) of the barrel in decimal
fractions of the inch or in millimetres. Some guns—such as shotguns—report the weapon's gauge
(which is the number of shot pellets having the same diameter as the
bore produced from one English pound (454g) of lead) 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.
USS Iowa (BB-61) fires a full broadside during a target exercise near Vieques Island, Puerto Rico, 1 July 1984.
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),
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 muzzle 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.
History
Main article: History of the firearm
Operating principle
Most 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 while 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 the optimal gunpowder,
like the optimal 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 shock wave at such high temperature and pressure is much
faster than that of any bullet, and would leave the gun as sound either through the barrel or the bullet itself rather than contributing to the bullet's velocity.
Types of guns
IOF .32 Revolver chambered in .32 S&W Long
Mamba Pistol 9×19 mm Parabellum automatic pistol
Lee-Enfield Jungle Carbine chambered in .303 British
Military firearms
Machine guns
Handguns
Autocannon
Artillery guns
Tank guns
Hunting guns
Guns for training and entertainment
See also
Citations and notes
- ^ Merriam-Webster, Inc. (1990). The Merriam-Webster's New Book of Word Histories. Basic Books. pg.207
- ^ Online Etymological Dictionary
- ^ Kelly, Jack. (2004). Gunpowder Alchemy, Bombards, & Pyrotechnics: The History of the Explosive that Changed the World. Basic Books. pg.31
- ^ Ibid:pg.31
- ^ Kelly, Jack. (2004). Gunpowder Alchemy, Bombards, & Pyrotechnics: The History of the Explosive that Changed the World. Basic Books. pg.30
- ^ Kelly, Jack. (2004). Gunpowder Alchemy, Bombards, & Pyrotechnics: The History of the Explosive that Changed the World. Basic Books. pg.32
- ^ Captive Bolt Stunning Equipment and the Law - How it applies to you (pdf)
References
- Lee, R.G., Introduction to battlefield weapons, systems & technology, Royal Military College of Science, Shrivenham, UK, Brassey's Publishers, Oxford, 1981
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