Metal Gear Solid 2: Sons of Liberty
Nice, but where's the trigger?
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The majorly-anticipated sequel to the bestselling Metal Gear Solid and a bestseller in its own right, Metal Gear Solid 2: Sons of Liberty continues the story of Solid Snake in 2007 as he attempts to infiltrate a tanker to obtain photographic evidence of a new model of Metal Gear, the series' eponymous bipedal armoured combat vehicle, aboard an ocean-bound tanker in the lower New York harbour. The mission fails spectacularly, leaving the player to control a freshly-minted Foxhound agent, codenamed Raiden, who is sent in to infiltrate an environmental cleanup plant located at the site of the Tanker sinking, two years on, to deal with a terrorist takeover by a group named the "Sons of Liberty" during a presidential inspection tour. As with Solid Snake's previous adventure, Raiden himself discovers much about his mission he was not initially told, and as the terrorists' machinations unfold, he is left to question everything he knew about his superiors' motives, the terrorists' true objective, and even his own identity.
The following weapons are used in the video game Metal Gear Solid 2: Sons of Liberty:
Metal Gear Solid 2 (referred to as MGS2 for the rest of this document) introduced a few new features with regards to ingame firearms over its prequel. The first and most obvious change was the addition of shooting from First-Person View (FPV) for all ingame weapons. Whereas FPV was used mostly to get a player-character's-eye view of an area in the previous installment and was used only for shooting with a few weapons, MGS2 allowed for players to aim and fire all its weapons in FPV. Unfortunately, due to the PS2 controller's gimmick of pressure-sensitive face buttons, aiming a fully-automatic weapon (among a few other miscellaneous actions, such as gently peeking through a locker's vent grille without noisily hitting the player character's head on the door while hiding in a locker) requires the player to half-hold the fire button, which, while not quite as easy to mess up as the throat-slitting CQC command in MGS3, is not particularly precise since the square button does not have a great deal of distance between half-pressed to aim and fully-pressed to fire. This also meant that the game's ports to other consoles without pressure-sensitive face buttons or the PC made aiming such weaponry without simultaneously firing it impossible. Aiming semi-automatic weaponry in this game, however, had a much easier method of simply holding the button to aim and releasing it quickly to fire; slowly letting pressure off the button will lower the weapon without firing it.
The introduction of FPV shooting was also accompanied by an emphasis on targeting specific body parts of enemies to achieve better results than centre-mass hits would. While this allowed for somewhat-realistic effects (such as a shot to the head or heart of an unarmoured NPC instantly killing that NPC), the developers went a degree further, to the point that ingame helmets of any kind were incapable of stopping bullets of any type, and hitting both of a human enemy's arms or legs with lethal bullets would cause most of them to count as "killed."
In addition to FPV and its related shooting mechanics, MGS2 was the first game in its series where player characters had the ability to use guns in melee attacks to subdue opponents with non-lethal force. Despite the series' tendencies towards realistically-depicted weaponry, MGS2 also started a long-running trend of many ingame characters firing unrealistically-long bursts from fully-automatic-fire-capable weapons during cutscenes, something that would continue to be featured throughout the rest of the Metal Gear Solid series despite the fact that no ingame weapon in this title is modelled with a large enough magazine to support such long bursts, and the fact that fully-automatic fire generally isn't recommended for most real-life applications due to its inaccuracy. Recoil-induced accuracy penalties are not modeled in this game for player characters (and a few bosses), however, so a long burst of fully-automatic fire will be just as accurate as single shots.
Solid Snake always begins the Tanker chapter of the game with a specially-modified Beretta M9 fitted with a suppressor and loaded with tranquilizer rounds that will knock out enemies. Otacon misidentifies it as a "M92F", but Snake corrects him that it is an M9. To keep noise down from cycling a new round, the slide is locked closed and Snake must cock the gun manually after every shot. It is also fitted with a laser sight attached to the trigger guard. If the Very Easy difficulty is selected when starting a new game, Raiden will start with the M9 already in his inventory at the beginning of the Plant Chapter. On Easy, the M9 is hidden somewhere in the first area of the game; higher difficulties require the player to search the warehouse in Strut F to find one. If contacted via CODEC, Iroquois Pliskin implies that the M9 located on the Big Shell was the result of Philanthropy fanboys replicating the M9 in honor of the failed Tanker mission. Some Marines in the Tanker chapter cutscenes are equipped with the weapon as well, but theirs do not have suppressors and are loaded with lethal rounds, which the player cannot use. Certain guards who are held up with this weapon will somehow recognize it as a tranquilizer weapon and thus will not give up their items unless the player switches to a lethal weapon instead.
This pistol is based on the Beretta XM9, a handgun that was made in collaboration with KAC. The suppressor is a quick-detach type that fits onto notches in the barrel, rather than being screwed onto a threaded barrel (as is more common with handgun suppressors). A device is fitted on the frame and locks into the slide stop and prevents it from reciprocating when the shot is fired (the real-life version allows for disengaging of the slide stop, but this ability is not emulated in game). After the shot is fired, the device slides out of the stop so that the slide can be manually racked to extract the spent casing.
Unlike many games of its time, the M9's Double-Action/Single-Action nature (in other words the gun can be fired without needing to cock the hammer, whereupon after the hammer will remain cocked for a lighter trigger pull until de-cocked) is emulated in this title. Accordingly, when a player character equips the M9, the hammer is shown as being uncocked, but when the slide is racked after the first shot, the hammer becomes cocked and remains so until the player character unequips (and presumably decocks) the weapon. However, the slide-racking animation has one unrealistic aspect; if the player character shoots the M9 and then quickly takes cover behind an obstacle that is very close to the player character while holding down the aiming/firing button (so that the player character points the M9 upwards while holding it in both hands) before the manual-slide-racking animation has a chance to play, the slide will reciprocate by itself without any action on the part of the player or the player character (the player character's hands will still be on the gun). This was most likely done to allow for more regular shots, without having to program an additional animation or forcing the player to wait for the manual-slide-racking animation to play first.
Olga Gurlukovich is seen with a PSS Silent Pistol. It is never given a chance to be used, however: She tosses the gun overboard shortly afterwards, after Snake orders her to do so. The player cannot obtain this weapon.
Heckler & Koch USP
Exclusive to the Tanker Chapter, Olga Gurlukovich uses a Heckler & Koch USP when dueling with the player. After defeating her, Snake automatically takes the empty gun (emptied by Olga, and made so by the programmers to avoid giving the player any ability to execute Olga and mess up the story) and uses it after acquiring ammunition for it. It can be fitted with a suppressor when playing the chapter for a second time in the "Substance" version of the game, and also comes with a tactical flashlight that turns on automatically when the weapon is drawn and readied in a dark area. Unfortunately, this becomes a hindrance when trying to keep a low profile. Its caliber is mentioned by Snake to be 9mm Parabellum, of which it can hold 15 in the magazine, or 15+1 when Snake performs a tactical reload. The script as well as Snake's reaction in the final game implied that the USP (a German-made gun issued to American forces) being used by Olga (a Russian) was unusual.
Sergei Gurlukovich is seen using a Makarov to hold Marine Commandant Scott Dolph hostage. Raiden also observes the other soldiers carrying Makarovs later in the game, but only use them when they run out of ammunition for their primary weapon, or sometimes when their right arm is injured. It is also used by soldiers wielding riot shields. This weapon cannot be obtained or used by the player.
Heckler & Koch Mark 23 Phase II Prototype
Raiden is given a Heckler & Koch Mark 23 Phase II Prototype by Iroquois Pliskin early in the Plant Chapter of the game during his first visit to Strut B. It is fitted with a LAM (Laser Aiming Module), though it is not used to aim in first-person mode (instead, the player aims using the iron sights, despite the laser still being turned on anytime the gun is aimed in first- or third-person view). It can be fitted with a suppressor found in Strut F after Raiden visits Strut C for the first time. It holds 12 rounds of .45 ACP ammunition with each magazine. The tactical light on the handgun cannot be used ingame, except for a few VR missions in the Substance version.
For some odd reason, Raiden always draws this weapon in cutscenes after obtaining it (unless the player has the M9 equipped before entering the cutscene, in which case Raiden will use that instead), even when going up against a foe who can dodge bullets, or against multiple opponents, both being situations for which an automatic firearm like the AKS-74U would be much better suited. The fact that Raiden is forced to obtain the AKS-74U (much like he cannot refuse to take the SOCOM pistol), coupled with his true combat experience which an AK would be more familiar to him, serve to highlight the oddness of this directorial decision to have Raiden always "bring a pistol to an assault rifle shootout" in cutscenes.
Colt Single Action Army
The Colt Single Action Army is the weapon of choice for Revolver Ocelot. Cannot be obtained by the player, and is fired in only four scenes in the game, half during the Tanker Chapter, and the other half during the Plant Chapter.
Ocelot first fires it on an unsuspecting Gurlukovich mercenary, after he caught him hiding, with Ocelot making clear that he intended for Gurlukovich himself to die shortly thereafter upon killing him.
True to his earlier vow, he next fired the Single Action Army on Sergei Gurlukovich and Scott Dolph (the latter being released by the former so he'd have a clear shot against Ocelot in revenge for his betrayal), also shooting right through the jacket to hit Gurlukovich in the lung and Dolph in the head. In the same scene, he also managed to kill about six to nine Gurlukovich mercenaries when they attempted to avenge their boss (technically, this should be impossible since the Single Action Army only has enough rounds for six shots at most).
He later used it to kill President James Johnson (ironically, just before he forced Raiden to pull the trigger to prevent Arsenal Gear from launching its nuclear payload), claiming that his actions were "an abuse" to the First Amendment right to free speech.
Lastly, he used it on Fortune to demonstrate that her "luck" was actually the result of an electromagnetic gizmo that deflects any and all bullets aimed at her, although he only mortally wounded her rather than instantly killing her due to her being born with dextrocardia.
The Glock 18C is Fatman's weapon of choice when he's not planting C4 explosives. It is modelled with what appears to be a 19-round magazine. He uses it in his battle with Raiden on occasion, calling it "a short recess on bombs." In the backstory he was known for disassembling and reassembling it whenever he had a spare moment, not being one to keep his hands still. Due to an animation oversight, Fatman can be knocked down in the middle of reloading after ejecting an empty magazine, but will still eject another one once he stands up again to resume reloading. Unlike other ingame enemies, Fatman does not appear to suffer any recoil-induced penalties to his accuracy whenever he fires in full-auto either.
This weapon made its first appearance in the Metal Gear Solid series, but would not become available to the player until the fourth game.
The Arsenal Tengus in Arsenal Gear are seen carrying and using FN P90 submachine guns (unobtainable by the player). Solidus Snake is also seen with one, which is somehow capable of penetrating the armor on a Metal Gear RAYs.
The AKS-74U is used by most of the Gurlukovich soldiers throughout the Tanker Chapter, and by the guards in the Shell 1 Core of the Plant Chapter, all of whom except for clearing team members use it in combination with a suppressor (likely to preserve their hearing when firing this weapon indoors). Raiden must obtain one of these in order to impersonate one of the aforementioned Shell 1 Core guards, but outside of Very Easy difficulty cannot acquire a suppressor for the rifle until he reaches the bridge connecting Shell 1 and 2. It is equipped with a laser sight for aiming, as the player cannot use the iron sights for that purpose.
In the Substance edition and HD re-release of MGS2, giant-sized Gurlukovich soldiers (individually named "Gurlugon") can be seen carrying giant AKS-74Us in the VR missions and one non-canonical "Snake Tales" extra mission, but never fire them, instead relying on other means of attack. Gurlugon monsters are also depicted with trefoil protrusions running in two lines down the backs of their heads to the rear of their pelvises, which is a clear reference to the Godzilla series of movies.
The M4A1 Carbine is seen throughout the game, carried by the Marines in the Tanker Chapter, the Navy SEAL Team 10 in the Plant Chapter, Pliskin himself, and certain clearing teams after Raiden's duel with Fatman. It can only be acquired by Raiden in the Plant Chapter in Strut F, and it comes with a laser sight. While the underslung M203 grenade launcher is used in conjunction with the M4A1 by one of the Marines aboard the tanker, certain Big Shell clearing teams, and by Snake in his fight with Solidus, it is not possible for the player to use in any way. The M203 is also memorably used against Fortune by a member of SEAL Team 10, where a grenade fired from it harmlessly lands at her feet as a dud.
The game lists this weapon as an M4, but its fully automatic fire makes it an M4A1, not an M4, which is limited to semiautomatic and burst-fire only.
The AN-94 assault rifle is used by the Gurlukovich soldiers patrolling many areas in the Plant Chapter, and by clearing teams in the earlier phases of that chapter. It cannot be obtained by the player.
In-universe, the AN-94 had been adopted as the "official rifle of the Russian Army" by the time when the Plant Chapter occurs in 2009. In reality, the AK-74M would still ultimately be the standard Russian Army assault rifle as of 2009. Many NPCs carrying the AN-94 use it along with a tactical flashlight.
The FAMAS bullpup rifle is not ordinarily available to the player in the final game and is only accessible via a cheat device used with the MGS2 demo disk. It can be seen in MGS1 gameplay videos appearing in cutscenes where Raiden mentions his VR training (implied to actually be from playing MGS1 and its bonus VR missions with VR gear), and also in the hands of Solid Snake in a flashback sequence depicting his escape from the sinking tanker. Pre-release trailers also showed Snake using a FAMAS on the Tanker, implying this weapon was at one point present there, and most likely the flashback is footage from an alpha or beta version of the level.
In the demo, the FAMAS is very inaccurate and has a few animation errors, most notably how Solid Snake keeps cocking the charging handle when firing it in First Person View. In the Substance version of the game, it is also seen in the hands of the hidden bosses of the added VR missions for Solid Snake, named Genola and Mech Genola. These two are essentially giant-sized, higher-detail Genome Soldiers in winter gear from MGS1, but they are never actually seen firing their giant-sized FAMAS rifles. One notable detail of their 3D models that was not made higher-detail for the Substance version are their fingerless mittens, raising the question of how they are supposed to properly fire their rifles without much freedom of movement for their trigger fingers.
"Genola" is reverse Pig Latin for "Enola Gay", the B29 bomber that dropped the "Little Boy" atomic bomb on Hiroshima.
Heckler & Koch PSG-1
Heckler & Koch PSG-1 semi-automatic sniper rifles equipped with dynamically zooming scope are used by both Raiden and Pliskin, exclusive to the Plant Chapter. A fictional variant firing tranquilizer rounds and equipped with a sound suppressor is available in Strut F or the flooded Shell 2 Core B1 area, named the PSG-1T.
The Franchi SPAS-12 is carried by the clearing teams in the Big Shell. It is never available to the player, and NPCs fire it slowly despite the real weapon's semiautomatic firing ability.
The FIM-92A Stinger surface-to-air missile launcher is exclusive to the Plant Chapter. The launcher has a lock-on function as well, strangely locking onto targets that do not possess any heat or radar signature the missile could realistically lock onto, such as human guards. Despite its supposed destructive power, nothing prevents the player from using it indoors, even inside the sections of the Shell 2 Core that are below the waterline, where blowing holes into the walls (logically resulting in flooding) would be most detrimental to Raiden's mission. As useful as this weapon may be in destroying vehicles, it is powerless to alter the game's environment in any way.
As in the first Metal Gear Solid, there is no animation for readying another Stinger and it is simply ready to fire again after a couple of seconds, not even requiring the player character to stop looking through the scope. It is also incorrectly shown with the missile seeking the instant it exits the launcher; the real Stinger flies straight for 660 feet before the seeker engages.
Croatian Milkor MGL clone in a six-shot revolver configuration, reloaded with a speedloader fitted for grenades. Exclusive to the Plant Chapter, and only available from Strut F once Raiden completes his objective in the second basement level of the Shell 1 Core. It is cumbersome to use given that the player cannot use the sights on the weapon, and that there is no arcing trajectory display in this game as in Metal Gear Solid 4 when a grenade is drawn and readied, though use of the lock-on feature will allow the player to compensate for its arcing trajectory so as long as the target is not behind cover or out of sight. While ostensibly loaded with anti-personnel grenades, it has the ability to damage vehicles such as a Harrier II jet or even Metal Gear Rays if a hit is scored.
A fictional missile launcher which fires remote controlled missiles with their own cameras that feed the warhead's visual data back to the player. While dubbed a "missile" launcher, the munitions launched by this weapon move slowly enough to be miniature hovering UAVs with contact-detonation warheads. Exclusive to the Plant Chapter, Raiden must use one to reach an objective in the Shell 2 Core, which is shutting down the electrified floor to reach President James Johnson - easier said than done given that the warheads cannot change altitude manually (they strangely do so on their own if they are piloted up a slanted vent, implying their vertical guidance is some kind of terrain-following system), have a limited supply of fuel, and become uncontrolled if Raiden suffers damage while using the launcher. Johnson's tendency to jump in front of the missile also does not help. The missile can only be fired indoors, which the game explains as being because the Sons of Liberty activated an electronic interference field around the Big Shell to prevent enemy UAVs from entering. Most likely the real reason is that the Nikita would otherwise allow the player to discover non-drawn surfaces of buildings in the various exterior maps.
While the following function of the launcher is not elaborated on in the game, Raiden can disregard all the precision-machined-high-technology this weapon encapsulates and use it in one of the most blatantly low-technological ways possible, by swinging the launcher as a large, unwieldy, club to whack guards (and one boss) around. It can often knock guards out in one well-timed swing or deal heavy stamina damage to a boss, even in the higher difficulty levels, and not harm its performance in any way while being used in this "warranty-voiding" fashion. The Stinger missile launcher by contrast cannot be used this way, since equipping it instantly switches to the scoped view.
To date, this game is the Nikita's last appearance in the Metal Gear Solid series.
M203 Grenade Launcher
The M203 Grenade Launcher was seen mounted on M4A1s utilized by both the SEAL Team 10 Bravo Squad, and by the attack teams. The former attempted to launch it at Fortune, but her "luck" renders the grenade a dud. Given her "luck" turns out to be a combination of a personal shield generator and what appears to be magic, it is not particularly clear why this actually happened; it cannot have been any kind of EMP-like effect, since the 40mm rounds for the M203 use a mechanical detonator (never mind that such an effect would also disable Fortune's radio and her railgun).
C4 explosives are utilized by both Raiden and Fatman, the latter's C4 also serve as a major plot point for the first act of the Plant mission, as Raiden and Iroquois Pliskin have to disarm them using a special "coolant spray" to freeze their detonators.
C4 blocks can be procured by the player and used to set traps or destroy certain objects and devices which are immune to conventional weaponry. Just like in Metal Gear Solid, the C4 blocks are set off in the order they were placed, and are stated to have a scrambler, in order to ensure that any wireless signals that are not the wireless detonator do not accidentally set it off.
Fatman's C4 charges are larger than normal. As a self-made man who worships his creator, he generally utilizes C4 that emits a specific, detectable vapor, as well as cologne left on them as a "calling card." In addition, he also carries a briefcase-sized C4 charge in some pocket dimension in his blast suit that is activated via a remote despite being inside his own clothes, and is also implied to have more than enough explosive power to destroy the entire Big Shell in one blow.
Semtex is utilized in both the Tanker and Plant Chapters, although it is never available to the player. Both instances have large charges rigged to wall-mounted infrared sensor rigs that automatically detonate the explosives should they be crossed. Solid Snake has to bypass these by shooting out the control boxes or crawling under the sensors in the Tanker Chapter. Precise why the terrorists rig up a system which will allow an intruder or particularly tall rat to accidentally kill all of them before they can complete their mission is not clear. Later, the Sons of Liberty also rig the connection bridge to the two shells at the Big Shell (and one room in the Strut F warehouse) with Semtex to deter would-be intruders, which Raiden deals with by destroying the control modules, one of which is for some reason mounted on top of a Cipher drone.
M18A1 Claymore Mine
A fictional variant of the M18A1 Claymore Anti-Personnel Mine is available in the game, exclusive to the Plant Chapter. Unlike real-life versions, they are invisible to the naked eye (the game mentions that they are "stealth-equipped", though their locations and sensor coverage are visble with a mine detector) and explode if someone walks into their cone of detection. Raiden can disarm them and use them for himself if he crawls over one from outside its cone of detection, and they are plainly visible to the player if Raiden plants them himself. They can also be seen with the "thermal goggles" (Infrared) during the plant level.
Three types of grenades can be used in this game. They are a generic frag grenade, a flashbang grenade, and a fictional chaff grenade.
The usage of the first two types is quite cumbersome compared to later instalments in this game series. To use one of them, the player must first press a button to ready the grenade (depicting the player character pulling the pin with his teeth), and then release the button to throw the grenade. The catch is that the player character doesn't hold onto the safety lever when the pin is pulled, and if it is not thrown it before the fuse runs out, the player character suffers painful consequences. What's worse is that the force at which the button is pressed determines the velocity of the grenade(using the PS2 controller's pressure-sensitive face buttons, rarely a good idea), which is not indicated on screen before the grenade is thrown and is in general difficult to get right without a lot of practice.
The chaff grenade avoids the problems of the aforementioned user-unfriendly grenade-throwing mechanic by virtue of being absolutely harmless and completely location independent. Regardless of where it is thrown (except into water), upon detonation it will release a great deal of radio-reflective fragments that temporarily blind all UAVs and security cameras in the current area, as well as temporarily jamming radio transmissions, so guards cannot call for backup if they spot you while the fragments are still suspended in the air. The chaff is even capable of slowing the reaction times of Metal Gear Rays.
The frag grenade acts more like a concussion grenade by killing with its explosive force rather than releasing visible fragments. The flashbang grenade instead creates a non-lethal explosion that stuns anyone caught in its blast radius, though the white flash seen while using flashbang grenades in later instalments of this series is not implemented in this game. Both types will cause an alert to be sounded in the area you are in if one is not already active, or if a chaff grenade's chaff is not still active.
Classic black-ball-with-prong-detonators underwater mines are found in the flooded area of the Shell 2 Core. It is implied that they are placed there by Vamp as obstacles for Raiden, though precisely why or where Vamp has them is not clear. According to Otacon, the mines contain built-in compound sensors that can track anything from something's acceleration speed to changes in the water pressure, and even body temperature, among other data. They obviously cannot be used by the player.
General Dynamics GAU-12/U
The "Sons of Liberty" group somehow has access to a US Marine Corps AV-8B Harrier II (likely due to Solidus Snake's backing, thanks to his previous role in civilian life mentioned by the game). The plane is technically a TAV-8B two seat trainer version, which is unarmed and incapable of mounting weaponry.
Among its arsenal of weapons are LAU-5003 rocket pods, AMRAAM air-to-air missiles (with Raiden apparently counting as an airborne target that can be tracked by its radar), CBU-100 cluster bombs and a General Dynamics GAU-12/U mounted on its underside. As is common for video game depictions of military vehicles, the Harrier's GAU-12/U and other weaponry are depicted as having infinite ammunition, while the real-life Harrier II only has enough room to carry 300 rounds. Despite presumably being loaded with armour-piercing depleted-uranium-tipped rounds capable of penetrating the top armour of tanks, the GAU-12/U is depicted as being completely unable to penetrate any form of cover, which is clearly a concession towards gameplay. The GAU-12/U is, however, modelled correctly, with a muzzle flash only emerging from the left-hand pod, since the right one contains the weapon's ammunition and retains the empty casings when the gun is fired so as to prevent them from being sucked into the Harrier's air intakes and causing damage to the engine.
The Harrier II itself is mentioned to have shot down the two cargo helicopters used by SEAL Team 10, but can first be seen on the heliport of Strut E; it disappears from that location during the Fatman boss fight, and is later faced as the second boss of the Plant Chapter. For some bizarre reason, Fatman sees fit to affix at least one of his C4 bombs on the Harrier's underside before his boss fight, which Raiden must freeze. Furthermore, if Raiden contacts the Colonel overseeing his mission about the Harrier, the Colonel will claim that the weapons Raiden has at that point "aren't up to the task of neutralizing this plane" (so as to prevent the player from removing it as a boss fight later). This is in spite of the fact that Raiden can obtain Claymore mines prior to this - one or more of them placed by hand into the air intakes and manually detonated would likely render the Harrier unflyable.
NRS-2 Scout Firing Knife
This obscure concealed Spetznaz firearm consists of a knife with a short barrel for a single SP-3 suppressed pistol cartridge in the grip, pointed in the opposite direction from the tip of the blade. Olga draws and fires it at Snake when ordered to throw it overboard, only for him to dodge it, which causes Snake to take cover anyway and give her an opportunity to draw her USP. Olga shortly afterwards claims that Snake is the first one to dodge a round fired from her scout knife before fighting him.
Fortune's Rail Gun
The only weapon used by Fortune is a fictional man-portable but large prototype railgun. It is equipped with a laser sight and a scope of undisclosed model, firing slugs of undisclosed size; a pistol-scale magazine is seen in Metal Gear Solid 4, which would imply they are not particularly large.
According to the Colonel that Raiden can contact for advice, the railgun accelerates projectiles to a high enough velocity to possess "ten megajoules of kinetic energy," incidentally half that of the "twenty megajoules imparted to the ammunition of a 140mm smoothbore gun" mentioned by the game. Presumably this is a reference to the scrapped NATO XM291 140mm gun project for the Abrams and Leopard 2 during the mid-80s (a response to reports that a "Future Soviet Tank" (FST) was under development with a 135mm or 152mm main gun and armour sufficient to require a muzzle energy of 18MJ to penetrate), though available information implies that the muzzle energy of this gun was actually 23 megajoules. Seemingly the only tanks ever to mount it were a single Abrams and a Swiss Pz87 (Leopard 2 A4), so it is curious it is mentioned; the plan was ultimately scrapped by the Germans in favour of the L/55 variant of the Rheinmetall 120mm gun, while the US designed more advanced kinetic energy rounds for the L/44.
Even if it is assumed the projectiles fired are as heavy as 20mm cannon bullets (100 grams), the railgun would still have to accelerate its ammunition to some 46,400 feet per second (a little shy of 42 times the speed of sound, which is about twice escape velocity, thus making it the first infantry weapon which could target satellites) to achieve this. The weapon never generates any deafening sonic booms despite accelerating projectiles to hypersonic speeds. Fortune herself never endures much recoil from using it, to the point that she is able to double-tap the rail gun in higher difficulty levels. She also experiences no fatigue or difficulty aiming it, despite the weapon being easily 5 feet in length, and nearly as tall as her. No power or coolant source on her rail gun requiring periodic replenishment is apparent either, despite the massive amounts of electricity (and the likely-to-be-high resulting levels of waste heat) electrically accelerating a projectile over such a short distance would require in a man-portable platform.
The weapon is said to have been abandoned because there is a high risk of "accidental discharge," but the weapon's actual behaviour and the further description (that there is some problem with the plasma and the rail failing to disconnect) suggests the actual issue is runaway fire, with the railgun's retractable armature returning to battery position while retaining enough charge to immediately launch a new projectile each time the action cycles. True to this, Fortune is able to fire the weapon repeatedly in bursts, her "luck" presumably causing the rail to disconnect from its powered position when she wants to stop firing. When seen in MGS4, the weapon requires charging up for each shot fired, implying the railgun was bought to heel by using a capacitor bank which is only sufficient for one shot and / or a weaker power source.
The railgun isn't actually wholly a digital creation; a physical prop was created from wood for motion capture sessions. The fearsome size of the railgun meant even this was rather on the heavy side, and Fortune's motion capture actress has stated she ended up "covered in bruises" every time she had to handle it.