Editing Automatic firearm (section)

{{Short description|Firearm that fires continuously while the trigger is depressed}}
[[File:M2 machine gun.jpg|thumb|220px|A [[M2 Browning]] [[machine gun]], surrounded by ejected cartridge cases]]

An '''automatic firearm''' or '''fully automatic firearm''' (to avoid confusion with [[semi-automatic firearm]]s) is a [[self-loading firearm]] that continuously [[Chamber (firearms)|chambers]] and fires [[Cartridge (firearms)|rounds]] when the [[trigger (firearms)|trigger]] mechanism is actuated. The [[action (firearms)|action]] of an automatic firearm is capable of harvesting the excess energy released from a previous discharge to feed a new [[ammunition]] [[cartridge (firearms)|round]] into the [[chamber (firearms)|chamber]], and then igniting the [[propellant]] and discharging the [[projectile]] (either [[bullet]], [[shot (pellet)|shot]], or [[shotgun slug|slug]]) by delivering a [[hammer (firearms)|hammer]] or [[firing pin|striker]] impact on the [[primer (firearms)|primer]].

If ''both'' the feeding and ignition procedures are automatically cycled, the weapon will be considered "fully automatic" and will fire continuously as long as the trigger is kept depressed and the ammunition feeding (either from a [[magazine (firearms)|magazine]] or a [[belt (firearms)|belt]]) remains available.  In contrast, a firearm is considered "[[semi-automatic firearm|semi-automatic]]" if it only automatically cycles to chamber new rounds (i.e. [[self-loading]]) but does not automatically fire off the shot unless the user manually resets (usually by releasing) and re-actuates the trigger, so only one round gets discharged with each individual trigger-pull.<ref name="Carter2012">
{{cite book|last=Carter|first=Gregg Lee
|title= Guns in American Society: An Encyclopedia of History, Politics, Culture, and the Law
|url= https://books.google.com/books?id=oD46JBOhMU0C&pg=PA53|year=2012|publisher=ABC-CLIO
|isbn=978-0-313-38670-1|page= 53
}}
</ref>  A [[burst mode (weapons)|burst-fire]] firearm is an "in-between" of fully and semi-automatic firearms, firing a brief continuous "burst" of multiple rounds with each trigger-pull, but then will require a manual re-actuation of the trigger to fire another burst.

Automatic firearms are further defined by the type of [[Action (firearms)#Autoloading operation|cycling principle]]s used, such as [[recoil operation]], [[blowback (firearms)|blowback]], [[blow forward]], or [[gas operation]].