Editing Railgun

{{Status|Canon}}
{{Wikipedia}}
[[File:Internet Railgun example.png|thumb|250px|Schematic diagram of a railgun]]
A '''railgun''', alternatively spelled '''rail gun''', is a type of electromagnetic projectile weapon. While often confused with [[coilgun]]s, rather than accelerating their projectiles through the use of magnetic coils, railguns, as their name suggests, utilize magnetic rails to perform this task. More precisely, a railgun accelerates a conductive projectile along a pair of metal rails, using two sliding or rolling contacts that permit a large electric current to pass through the projectile. This current interacts with the strong magnetic fields generated by the rails and this accelerates the projectile.

A handful of railguns are used by the armed military forces of [[human]]ity, including those of the [[United Nations Space Command]] and [[Colonial Military Authority]]. They are predominantly mounted on vehicles for use as fixed artillery emplacements, and can be divided into two broad categories - Light and Heavy Railguns, respectively. They may also fall under the broader umbrella classification of "[[Magnetic Accelerator Cannon]]" - a term used by human military forces to refer to larger emplacements employing electromagnetism in their operating function. Most MACs used by humanity are the primary armaments on [[UNSC starship|warships]] and are more often seen using coilguns as their operation, with railgun MAC artillery mostly found on fixed ground emplacements and vehicles.

==Types of railguns==
===Light railguns===
Light railguns (LRGs) in human service are primarily found on [[tank]]s - notably the [[SP42 Cobra]] main battle tank in CMA service throughout the 25th century.{{Ref/Book|Id=EVGCobra|EVG|Page=32}}{{Ref/Book|Id=HWSGCobra|Halo Wars: Official Strategy Guide|Page=43}}{{Ref/Book|Id=Enc22Cobra|Enc22|Page=142}} They are generally designated using the standard ''MXX'' nomenclature, with the ''XX'' representing two digits of unknown significance. The known examples of LRGs in service have designation styles similar to the series of [[Gauss cannon]]s commonly found mounted on [[M12 Warthog]] FAVs (eg the [[M65 Gauss cannon|M65]], [[M68 Gauss cannon|M68]], [[M68B Gauss cannon|M68B]], and [[M70 Gauss cannon|M70]] models).
*'''[[M66 light railgun|M66 30cm light railgun]]''' - secondary railgun armaments on the SP42 Cobra MBT,{{Ref/Reuse|EVGCobra}}{{Ref/Reuse|Enc22Cobra}} alongside an optional mounting on [[M5 Talos|prefabricated base turret]] systems such as the [[M5 Talos]] for anti-vehicle munitions.{{Ref/Book|Halo Wars: Official Strategy Guide|Page=30}}{{Ref/Game|HW2|Base Turret anti-vehicle upgrade}}
*'''[[M98 light railgun|M98 105mm light railgun]]''' - primary armament on the SP42 Cobra MBT.{{Ref/Reuse|EVGCobra}}{{Ref/Reuse|Enc22Cobra}}

<gallery>
File:HW_Cobra_Concept_2.jpg|The twin M66 LRGs on the SP42 Cobra.
File:HW-RefineryBattle-SP42CobraMBT.jpg|Deployed SP42 Cobras in their "lockdown" state, firing their M98 LRGs.
</gallery>

===Heavy railguns===
UNSC heavy railguns (HRGs{{Ref/Book|H4EVG|Section=Glossary|Page=228}}) follow a similar style of nomenclature to the "[[Onager]]" series of [[mass driver]]s, generally styled as ''Mark XXXX'', where ''XXXX'' denotes the year of service for the design. This is followed by the bore size of the weapon in question, usually denoted in centimetres. Heavy railguns are generally mounted on the heaviest ground vehicles and walkers humanity has available, and may be informally referred to as "mini-MACs" by ground crews.{{Ref/Level|H4|Reclaimer (level)|Reclaimer}}{{Ref/Book|Id=Enc22Mammoth|Enc22|Page=144}}{{Ref/Site|Id=Guide|URL=http://www.halowaypoint.com/en-us/intel/inteldetail/2b6db073-56ae-4248-b2e1-e7615eaf22bb/mammoth|Site=Halo Waypoint|Page=Halo 4 Interactive Guide - Vehicles: Mammoth|D=04|M=05|Y=2013|LocalArchive=Halo 4 Interactive Guide#Vehicles}}
*'''[[Mark 2547 heavy railgun|Mark 2547/35cm heavy railgun]]''' - primary artillery emplacement on the [[M510 Mammoth]].{{Ref/Reuse|Enc22Mammoth}}{{Ref/Reuse|Guide}}
*'''[[Mark 2555 heavy railgun|Mark 2555/20cm heavy railgun]]''' - primary artillery emplacement on the [[HRUNTING/YGGDRASIL Mark II (J) Colossus]],{{Ref/Book|Id=Enc22Colossus|Enc22|Page=146}} and originally designed for use on emplaced and fortified structures.{{Ref/Game|HW2|Phoenix Logs|Detail=Colossus}}
<gallery>
File:H4_Mammoth_Render_2.jpg|The Mark 2547/35&nbsp;cm HRG is the primary armament of the M510 Mammoth.
File:HW2 Blitz Colossus.jpg|A Colossus walker sporting a Mark 2555/20&nbsp;cm heavy railgun.
</gallery>

===Infantry-portable railguns===
Due to the power requirements required of EM weapons, they have traditionally been an uncommon sight in the hands of infantry, with the [[M99 Stanchion]] line of portable gauss rifles being one of the only examples of such weapons in active service during the [[Insurrection]]. Infantry-portable railguns have been in service for decades with several lines in full production.{{Ref/Book|H4EVG|Page=63}} Thanks to a handful of breakthroughs made during the [[Human-Covenant War]], the '''[[ARC-920 railgun|Advanced Recoilless Carbine-920]]''' was introduced following the war's end as one of several limited production runs of various recoilless carbines intended for use by [[Spartan Operations]] personnel - considered too bulky and unwieldly for general use. Despite this, the ARC-920 is generally considered to be the best of the railgun offerings available to infantry ground forces.{{Ref/Site|URL=https://www.halowaypoint.com/en-us/universe/weapons/railgun|Site=Halo Waypoint|Page=Railgun|D=30|M=09|Y=2021}}
<gallery>
File:H5G-Linda&ARC920.png|An ARC-920, as used by [[Linda-058]].
</gallery>

==Trivia==
UNSC [[naval autocannon]]s have erroneously been referred to as railguns on several occasions. Naval autocannons are generally large coilgun batteries used as naval artillery aboard warships. Such examples include concept art for {{UNSCShip|Andraste}} produced for ''[[Halo 3]]'' and later used in ''[[Halo: Reach]]'' as the basis for the {{Class|Paris|heavy frigate}}, which labels the ship's [[M870 Rampart point defense gun]]s as railgun turrets. 

''[[Halo: Warfleet – An Illustrated Guide to the Spacecraft of Halo]]'' also erroneously refers to its [[Castor naval coilgun|Mark 55 Castor naval coilguns]] as railguns in the double-page spread for the {{Class|Strident|heavy frigate}}, with the same spread also labelling the weapon as a naval ''coil''gun.{{Ref/Book|HWF|Page=39}}

An "Arm-Mounted Railgun" was one of several [[Cut Halo 5: Guardians weapons|cut weapons]] concepted during the [[Development of Halo 5: Guardians|production]] of ''[[Halo 5: Guardians]]''. The concept produced by [[:Category:Images by Paul Richards|Paul Richards]] depicts a [[Pelican]]-mounted railgun equipped like a support weapon for use by Spartans.{{Ref/Site|URL=https://thepaulrichards.tumblr.com/post/131981842894/for-freelance-inquiries-contact-paul-richards-at|Site=Tumblr|Page=Paul Richards|D=26|M=01|Y=2021}}

==Gallery==
<gallery>
File:H3_UNSCAndraste_Concept.png|UNSC ''Andraste'' concept art for ''Halo 3'', falsely labelling the M870 Rampart PDGs as railgun turrets.{{Citation needed|reason=We require proof that Charon-class light frigates were not intended to be outfitted with railguns at this point of Halo 3's development.}}
File:H4 RailgunDLC Concept.jpg|''Halo 4'' concept art for a large UNSC railgun turret, the intended setting of a [[Cut Halo 4 levels|cut DLC map]].
File:H5G_ArmMountedRailgun_Concept.jpg|Concept art for the UNSC railgun weapons cut from ''Halo 5: Guardians''.
</gallery>

==List of appearances==
*''[[Halo Wars]]'' {{1st}}
*''[[Halo 4]]''
**''[[Spartan Ops]]''
*''[[Halo: Spartan Assault]]''
*''[[Halo: Escalation]]''
*''[[Halo: Mortal Dictata]]'' {{Mo}}
*''[[Halo 5: Guardians]]''
*''[[Halo Wars 2]]''

==Sources==
{{Ref/Sources}}
[[Category:Railguns|Railguns]]
[[Category:Magnetic acceleration weapons]]