Active-shooter drills in schools may do more harm than good

Active-shooter drills in schools expose students to frighteningly realistic scenarios with masked intruders and loud gunfire sounds. They also may be doing more harm than good, says a Rutgers University–Camden nursing scholar ...

Keeping guns away from potential mass shooters

The United States currently averages 20 mass shootings per year. Researchers from Michigan State University measured the extent to which mass shootings are committed by domestic violence perpetrators, suggesting how firearm ...

Strategies to lower risk for violent crime and gun violence

With violent crimes and gun violence rising annually and the number of gun deaths in the U.S. surpassing all other nations, researchers at the annual meeting of The Society for Risk Analysis (SRA) present a series of studies ...

Magneto-inertial fusion experiment nears completion

Assembly of the Plasma Liner Experiment (PLX) at Los Alamos National Laboratory is well underway with the installation of 18 of 36 plasma guns in an ambitious approach to achieving controlled nuclear fusion (Figure 1). The ...

Americans prefer gun control, but few prioritise it

As the US Congress returns from its August recess, Republican leaders have promised to work with Democrats to place gun control front and centre. Possible items on the agenda include enacting stronger background checks and ...

page 1 from 18

Gun

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.

This text uses material from Wikipedia, licensed under CC BY-SA