History Main / GunsFiringUnderwater

In Real Life, this trope can vary. Most guns will jam or misfire when people discharge them underwater. It's not the gun itself that is affected (well, not for the first time, anyway) -- it's the ammunition itself. Even if the gun is somewhat water-resistant (and that's a big somewhat, given that the barrel of a gun is essentially a giant hole), the primer of the ammunition is not. Besides the possibility of the primer being waterlogged, the gun's inner workings could also end up corroded by the water, and attempting to [[OhCrap fire a corroded gun is a Very Bad Idea.]]

Also a case of DoNotTryThisAtHome, because [[CaptainObvious guns are not intended to be fired underwater]]. Shooting a gun filled with water or wet ammunition is probably not going to end well for you or anyone around you. And shooting a gun underwater with air in its barrel is even worse, because the gun can explode.

* The climactic fight of ''Film/{{Mindhunters}}'' downplays this: the heroine and the SerialKiller BigBad both pack Glocks and both shoot at each other while struggling underwater, but while the Glocks shoot all right, the bullets just lose all of their velocity the moment they leave the barrel. The two of them are then forced to keep the guns ''out'' of the water and the fight then becomes a test to see who can hold their breath the longest, with the stakes of the loser being shot the moment they have to emerge.

* ''VideoGame/AlterAila'': In the Underwater Facility, you can fight enemies while underwater - and the battle screen doesn't reflect the battle being under water. This means that you can use all the regular weapons that you'd be able to use normally.[[note]]Like Shotguns and such.[[/note]]
* ''VideoGame/CallOfDutyGhosts'': This is a JustifiedTrope. As for the underwater missions "Atlas Falls" and "Into the Deep" Logan starts of with the APS Underwater Rifle for obvious reasons.
* Justified in ''VideoGame/DeathInTheWater'' with the krakken, an underwater shotgun. The weapon is a high-tech piece of hardware meant to function in the deepest trenches.
* ''VideoGame/DeltaForce'''s standard guns won't fire underwater, which is a nice touch considering how little time players will actually spend swimming. The second game introduces a pistol and an assault rifle specifically for underwear combat, [[CripplingOverspecialization but they're notably inferior to standard guns]].
* ''VideoGame/DeepBlackReloaded'' is a third-person shooter that's mostly set underwater, and all your guns follows this trope to a T, firing effectively without any problems in the abyss.
* Guns won't work underwater in ''VideoGame/DeusEx'', so you'll want a melee weapon for dealing with critters in the sewers.
* ''VideoGame/HalfLife1'': One of the advantages of the Glock (the game's starting handgun) is the capacity to fire underwater. It is one of only three weapons (the others being [[CrowbarCombatant the crowbar]] and [[TheStraightAndArrowPath the crossbow]]) that can be used in such scenarios, and this characteristic carries over to its equivalent in ''VideoGame/HalfLife2'', the USP Match.

* ''VideoGame/PlayerUnknownsBattleGrounds'': The player can swim through the water and their guns can fire as though nothing happened.

* ''VideoGame/RedOcean'' downplays the trope, but it's still there in stages where you need to go underwater to access a different part of the terrorist UnderwaterBase. Your guns can't fire underwater (though underwater areas never contain enemies) and as you surface in areas with enemies, your firearms can somehow work perfectly without clogging issues, despite being underwater literally seconds ago.
* ''VideoGame/SeaOfThieves'': All the guns is the game fire perfectly fine underwater, made more egregious by the fact that they're all powder weapons and shouldn't even be able to fire because the ammo is wet.

[[folder:Tabletop Games]]
* Played with in ''TabletopGame/BluePlanet''; most modern guns use electrically-ignited binary propellants and work just fine underwater, or can be made to with a minimum of fuss. (Corrosion's a problem, but [[FesteringFungus it happens on land too]].) That being said, water pressure does horrible things to external ballistics; range penalties pile up fast, on top of a penalty for being underwater at all.
* ''TabletopGame/{{Pathfinder}}'': Firearms can't be used underwater unless protected with specific magic, and even then, shooting through water imposes a stiff penalty on the weapon's accuracy. Early ammunition is ruined outright by exposure to water.
* ''TabletopGame/{{Shadowrun}}'': Averted, as there are rules for how bullets work underwater (generally, they don't) and there are a few weapons that have been specifically designed for underwater combat, including a carbine.
[[/folder]]

* Played with by the Soviet [[https://en.wikipedia.org/wiki/APS_underwater_rifle APS underwater rifle,]] which is {{exactly what it says on the tin}}: An assault rifle for combat underwater, firing steel darts that resemble those fired by a [[HarpoonGun Spear Gun]]. It was originally designed for the use by divers guarding important underwater infrastructure, after NATO successfully tapped underwater telephone cables carrying military comms and prompted the Soviets to start having their own frogmen carry out patrols. It was also issued to Spetznas for their own combat diver teams, but they quickly discovered it suffered from CripplingOverspecialisation: Out of the water its range and accuracy were poor. The [[https://en.wikipedia.org/wiki/ASM-DT_amphibious_rifle ASM-DT amphibious rifle]] and [[https://firearmcentral.fandom.com/wiki/AFM-DT AFM-DT carbine,]] which could fire the same darts as the APS but also load standard 5.45x39mm bullets, was developed to meet demand for a dual-purpose weapon. Later the [[https://en.wikipedia.org/wiki/ADS_amphibious_rifle ADS Amphibious rifle]] was developed which could use both standard 5.45mm ammo as well as special 5.45x39mm M74 7N6 cartridges meant for firing underwater.
* Underwater firing pistols have also been developed, the most popular being the Soviet [[https://en.wikipedia.org/wiki/SPP-1_underwater_pistol SPP-1 underwater pistol]] and the [[https://en.wikipedia.org/wiki/Heckler_%26_Koch_P11 Heckler & Koch P11.]] The SPP-1 has four shots and can be reloaded via clips that hold its 4.5mm cartridges together, while the P11 uses a pre-loaded five round cylinder that must be replaced by the manufacturer in order to be reloaded. Pistols are often preferred because they waste less space for such a niche weapon.
* Some people just ''had'' to try firing [[http://douglas-self.com/MUSEUM/COMMS/underwtrgun/underwtrgun.htm ship-board artillery underwater.]] Unsurprisingly it didn't work, but the idea did lead to the far more practical concept of the torpedo.

[[folder:Anime and Manga]]

[[folder:Films -- Live-Action]]

* ''Film/ShootToKill''. FBI Agent Stantin shoots the killer during an underwater struggle at point-blank range, avoiding the bullet diversion problem.

* In ''VideoGame/MightAndMagic VII'', the closest thing to a gun is the ''only'' weapon that can be used underwater, though being LostTechnology {{Ray Gun}}s it can probably get away with it (it is a bit more odd that you can't use spears). Conversely, the underwater area in ''VIII'' imposed no restrictions at all, but being the Elemental Plane of Water it isn't quite working on the same rules as normal water to start with.

* Played with in ''TabletopGame/BluePlanet''; most modern guns use electrically-ignited binary propellants and work just fine underwater, or can be made to with a minimum of fuss. (Corrosion's a problem, but [[FesteringFungus it happens on land too]].) That being said, water pressure does horrible things to external ballistics; range penalties pile up fast, on top of a penalty for being underwater at all.

* ''VideoGame/HalfLife1'': One of the advantages of the Glock (the game's starting handgun) is the capacity to fire underwater. It is one of only three weapons (the others being [[CrowbarCombatant the crowbar]] and [[TheStraightAndArrowPath the crossbow]]) that can be used in such scenarios.

[[/folder]]

* While dedicated underwater weapons have been developed as noted below they have never been used in combat, as the odds of two groups of divers encountering each other is almost nonexistent. Most potential targets have anti-diver defenses mounted on the surface, while divers themselves will be in trouble if they are found, and so few of them really bother to carry weapons for this purpose.

* Some people just ''had'' to try firing [[http://douglas-self.com/MUSEUM/COMMS/underwtrgun/underwtrgun.htm ship-board artillery underwater.]]

* Played with by the Soviet [[https://en.wikipedia.org/wiki/APS_underwater_rifle APS underwater rifle,]] which is {{exactly what it says on the tin}}: An assault rifle for combat underwater, firing steel darts that resemble those fired by a SpearGun. It was originally designed for the use by divers guarding important underwater infrastructure, after NATO successfully tapped underwater telephone cables carrying military comms and prompted the Soviets to start having their own frogmen carry out patrols. It was also issued to Spetznas for their own combat diver teams, but they quickly discovered it suffered from CripplingOverspecialisation: Out of the water its range and accuracy were poor. The [[https://en.wikipedia.org/wiki/ASM-DT_amphibious_rifle ASM-DT amphibious rifle]] and [[https://firearmcentral.fandom.com/wiki/AFM-DT AFM-DT carbine,]] which could fire the same darts as the APS but also load standard 5.45x39mm bullets, was developed to meet demand for a dual-purpose weapon. Later the [[https://en.wikipedia.org/wiki/ADS_amphibious_rifle ADS Amphibious rifle]] was developed which could use both standard 5.45mm ammo as well as special 5.45x39mm M74 7N6 cartridges meant for firing underwater.
* Underwater firing pistols have also been developed, the most popular being the Soviet [[https://en.wikipedia.org/wiki/SPP-1_underwater_pistol SPP-1 underwater pistol]] and the [[https://en.wikipedia.org/wiki/Heckler_%26_Koch_P11 Heckler & Koch P11.]] The SPP-1 has four shots and can be reloaded via clips that hold its 4.5mm cartridges together, while the P11 uses a pre-loaded five round cylinder that must be replaced by the manufacturer in order to be reloaded.

However, there ''are'' some RareGuns that have been designed to work underwater. These include the Heckler and Koch P11 pistol and the [[ExactlyWhatItSaysOnTheTin APS Underwater Assault Rifle.]]

* ''VideoGame/{{Alter Aila}}'': In the Underwater Facility, you can fight enemies while underwater - and the battle screen doesn't reflect the battle being under water. This means that you can use all the regular weapons that you'd be able to use normally.[[note]]Like Shotguns and such.[[/note]]

* ''VideoGame/HalfLife1'': One of the advantages of the Glock (the game's starting handgun) is the capacity to fire underwater. It is the only other weapon (the [[CrowbarCombatant crowbar being the other]]) that can be used in such scenarios.