Editing Action (firearms) (section)

===Autoloading operation===
[[File:Firearm operating systems Public Domain CC0 by Grasyl.svg|thumb|250px|Schematic of automatic firearm operations]]
====Blowback operation====
{{Main|Blowback (firearms)}}
[[File:FAMAS Bolt-gr.PNG|thumb|right|A schematic of the lever-delayed blowback mechanism used in the FAMAS assault rifle]]
The '''blowback operation''' is a system in which [[semi-automatic firearm|semi-automatic]] and [[fully automatic firearm]]s operate through the energy created by combustion in the chamber and bore acting directly on the bolt face through the cartridge. In blowback operation the bolt is not locked to the chamber, relying only on spring pressure and inertia from the weight of the bolt to keep the action from opening too quickly. Blowback operation is used for low-powered cartridges due to the weight of the bolt required.

Delayed blowback actions use some mechanism to slow down rearward travel of the bolt, allowing this action to handle more powerful ammunition and/or reduced weight of the bolt.

=====Examples of blowback operation=====
*'''Simple blowback''': [[Halcón M-1943]], [[Uzi submachine gun]], Varan PMX-80
*'''Advanced primer ignition''': [[Becker Type M2 20 mm cannon|Becker Type M2]], [[Oerlikon 20 mm cannon|Oerlikon 20 mm]], [[Mk 19 grenade launcher]], [[Atchisson AA-12]], [[Norinco LG5 / QLU-11|QLU-11 (LG5)]]
*'''Lever-delayed blowback''': [[FAMAS (rifle)|FAMAS]], [[Sterling 7.62]], [[AA-52]], 2B-A-40, [[TKB-517]]
*'''Radial-delayed blowback''': [[CMMG MkG]]
*'''Roller-delayed blowback''': [[SIG 510]], [[Heckler & Koch MP5|HK MP5]], [[Heckler & Koch P9|HK P9]], [[Heckler & Koch G3|HK G3]]
*'''Gas-delayed blowback''': [[Volkssturmgewehr 1-5]], [[Heckler & Koch P7|HK P7]], [[Steyr GB]]
*'''Primer-actuated unlocking''': Garand Model 1919, Postnikov APT, Springfield 1903 primer-actuated rifle and Clarke carbine
*'''Toggle-delayed blowback''': [[Schwarzlose MG M.07/12]], [[Luger rifle]] and [[Pedersen rifle]]
*'''Screw-delayed blowback''': [[Salvator-Dormus M1893]] & [[Demro TAC-1]] (Helical screw), Sheppard automatic rifle and [[Thompson Autorifle]] (Turnbolt)
*'''Blish Lock''': early [[Thompson submachine gun]]s
*'''Hesitation locked''': [[Remington Model 51]] and [[Remington R51|R51]] pistols, [[M50 Reising]], [[SIG MKMO]] and [[Armalite AR-18|Rudd Arms AR-180]]
*'''Flywheel-delayed blowback''': [[Barnitzke machine gun]], Kazachok SMG, and MGD PM-9 
*'''Detent-delayed blowback''': Show Low Manufacturing Black-Jack 
*'''Chamber-ring delayed blowback''': [[Seecamp]] pistol
*'''Pneumatic-delay''': [[Suomi KP/-31]] and Moore submachine gun

====Blow-forward operation====
{{Main|Blow forward}}
The '''blow-forward''' operation uses a fixed breech and moving barrel that is forced forward relative to the breech by the friction of the projectile against the bore as well as the breech recoiling away from the barrel.  The barrel is spring loaded and returns automatically to chamber a fresh round from the magazine.<ref>{{cite book |last=Cunningham |first=Grant |url= |title=Gun Digest Shooter's Guide to Handguns |publisher=Gun Digest Books |year=2012 |isbn=978-1-4402-3276-3 |location=Iola, Wisconsin |page=22}}</ref> Examples of this action are the [[Steyr Mannlicher M1894]], [[Hino Komuro M1908 Pistol]] and the [[Schwarzlose Model 1908]].

====Recoil operation====
{{Main|Recoil operation}}
The '''recoil operation''' is a type of [[locked-breech]] action used in semi-automatic and fully automatic firearms. It also uses energy from the combustion in the chamber acting directly on the bolt through the cartridge head, but in this case the firearm has a reciprocating barrel and breech assembly, combined with a bolt that locks to the breech. The breech remains locked as the bolt and barrel travel rearward together for some distance, allowing pressure in the chamber to drop to a safe level before the breech is opened.

=====Examples of recoil operation=====
*'''Short-recoil''': [[M1911 Colt pistol|Colt M1911]], [[MAB PA-15]], [[Browning Hi-Power]], [[Heckler & Koch USP|HK USP]], [[Glock pistol|Glock]], [[Mamba Pistol]], [[M2 Browning machine gun]], [[MG42]], [[Vz. 52 (pistol)|Vz 52 pistol]], Revol Arms DL45, [[M82 Barrett rifle|M82]]
*'''Long-recoil''': [[Browning Auto-5|Browning Auto 5]], [[Frommer Stop|Femaru STOP Pistol]], [[Mars Automatic Pistol]], [[Chauchat]]
*'''Inertia''': [[Sjögren shotgun|Sjögren Inertial]], certain [[Benelli (firearms)|Benelli shotguns]]

====Gas operation====
[[File:DIRECTM16.gif|thumb|250px|direct impingement]]
[[File:Kinematik Gasdrucklader Rückdrucklader mit Kammereinleitung.svg|thumb|250px|fluted chamber direct impingement]]
{{Main|Gas-operated reloading|Direct impingement}}
The '''gas operation''' is a system of operation mechanism used to provide energy to semi-automatic and fully automatic firearms. In gas-operation, a portion of high pressure gas from the cartridge being fired is tapped through a hole in the barrel and diverted to operate the action. There are three basic types: long stroke gas piston (where the gas piston goes the same distance as the operating stroke of the action parts, and is often attached to the action parts), short stroke gas piston (where the gas piston travels a shorter distance than the operating stroke of the action parts), and direct impingement (AKA "direct gas", "gas impingement", where there is no piston, and the gas acts directly on the action parts). A fourth type, now considered obsolete and ineffective, are those systems based on the Bang rifle that utilize a muzzle cap to capture gas after the bullet has left the barrel. While this system is successful in boosting the operating power of recoil operated guns, it is insufficient and too susceptible to fouling for use as the primary operating system.

=====Examples of gas operation=====
*'''Short-stroke gas piston''': [[FN FAL]], [[Sterling SAR-87|SAR-87]], [[Heckler & Koch G36|HK G36]]
*'''Long-stroke gas piston''': [[M1 Garand]], [[AK-47]], [[FN FNC]]
*'''[[Direct impingement]]''': [[MAS 49]], [[M16 rifle|M16]], [[AG-42]]
*'''[[Gas trap]]''': [[Gewehr 41]], [[Bang M1922 rifle]]<ref>{{cite web|url=http://www.nps.gov/spar/historyculture/exper-semi-auto-rifles-1919-31.htm|title=Experimental semi-automatic rifles, 1919-1931- excluding Garand's and Pedersen's rifles – Springfield Armory National Historic Site (U.S. National Park Service)|website=www.nps.gov|access-date=2009-06-28|archive-date=2009-12-02|archive-url=https://web.archive.org/web/20091202235030/http://www.nps.gov/spar/historyculture/exper-semi-auto-rifles-1919-31.htm|url-status=live}}</ref>