The M249 Squad Automatic Weapon (M249 SAW) is the United States military designation for a sub-family of the FN MINIMI squad automatic weapon (from Mini-mitrailleuse French: "mini-machine gun". Both are 5.56x45mm NATO light machine guns manufactured by Fabrique Nationale (FN) and its subsidiaries.

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Stands for Squad Automatic Weapon, and its main role is suppresive fire power, thats why no one who actually uses it in combat ever complains about that fact that it does'nt shoot machine gun rounds, it still makes the bad guys spend more time faceplanting themselves into a corner, and less time shooting at you.

The Gatling gun (1861) was one of the most well known rapid-fire weapons to be used in the 1860s by the Union forces of the Civil War, following the 1851 invention of the mitrailleuse by the Belgian Army. Although the first Gatling gun was capable of firing continuously, it required human power to crank it; as such it was not a true automatic weapon. Each barrel fired a single shot as it reached a certain point in the cycle after which it ejected the spent cartridge, loaded a new round, and in the process, cooled down somewhat. This configuration allowed higher rates of fire without the problem of an overheating single barrel. Some time later, Gatling-type weapons were invented that diverted a fraction of gas from the chamber to turn the barrels. Later still, electric motors supplied external power. The original Gatling gun was designed by the American inventor Dr. Richard J. Gatling in 1861 and patented in 1862.[1] He wrote that he made it to reduce the size of armies and so reduce the number of deaths by combat and disease.

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