Models and types of guns that saw little to no production in reality are more likely to show up in fiction. Sometimes, the number of appearances of a weapon in a given work can outnumber its actual production run.
This is mostly because some models of gun can look incredibly cool or futuristic despite having real-life problems with their functionality or production that make them unpopular, uncommon, or dismal failures. Or it could be a case of a writer wanting to show they did their research by deliberately picking form over function without going completely into the realm of fiction. Of course, no one's supposed to care. Alternately, some authors may simply wish to avoid associating a fictional character or group with real-world products, and so choose abandoned concepts and rare weapons with less economic and political baggage.
Remember that this trope is not about rare guns that appear once or twice in a work of fiction, or are an available weapon in a game. It only applies to rare weapons that appear in much larger numbers than they should or did in the real world, or firearms that are prohibitively expensive, difficult to use, or otherwise impractical but yet appear in the hands of many characters. A common justification is that the wielder/orderer of these weapons has an astounding amount of money, is extremely skilled with it, or it has become increasingly successful.
This trope is exceedingly common in video games* , due to the obsession many programmers have with technical and historical details. They also have the advantage of being able to include anything they want without worrying about the inability to get their hands on a real example. Anything that can be modeled is fair game for inclusion, whereas in live-action productions either acquiring an example or building a convincing look-alike as a prop is necessary. For the same reason, rare guns are also a staple of gun-oriented anime & manga, as artists can draw what they want without running afoul of Japanese gun control laws.
For less-rare guns, see Cool Guns.
See also Improperly Placed Firearms, Family-Friendly Firearms, Rare Vehicles, and Improbable Use of a Weapon. Compare Selective Historical Armoury, where firearms that should be present are absent. See also the Internet Movie Firearms Database site for more. This Youtube channel, appropriately titled "Forgotten Weapons", also has plenty of footage of obscure firearms. Similarly, champion shooter Jerry Miculek's Youtube channel includes a series of videos called "Unicorn Guns" in which Jerry profiles and sometimes gets to shoot rare guns, including some so rare as to be literally unique.
- Machine Pistols
- Submachine Guns
- Assault Rifles
- Battle Rifles
- Sniper Rifles
- Machine Guns
- Rockets, Missiles and Grenade Launchers
Misc Single Examples
- Sword Art Online: Alternative Gun Gale Online has a 7.62x39mm Krebs Custom KTR-09 assault rifle in the hands of Pitohui during the Squad Jam 2 tournament. Krebs rifles are custom-made AK-pattern rifles by Marc Krebs, who is regarded as one of the finest AK gunsmiths in America. The KTR-09 model was built off of the Russian Saiga platform starting in 2009 (hence the model number), and sold for high prices during the early 2010s. Unfortunately, the U.S. sanctions that were placed against Russia due to the Crimea annexation have blocked imports of Saiga firearms and led to Krebs discontinuing the KTR-09. Not that it was ever common in the first place, as it commanded a high price even when Krebs was actively making them.
- Dylan Dog owns an antique Bodeo Modello 1889-and not in Italy, where it could be relatively common having been standard issue for about fifty years, but in Britain. Endlessly Lampshaded by anyone who recognizes it, who invariably asks why he still uses one, how did he get one, or where does he get the munitions (Dylan knows a guy that makes them specifically for him, and found the gun in a cave. How it got there remains a mystery).
- A special story set in Victorian London has Dylan still armed with the Bodeo, then state-of-the-art. Upon reveal he's immediately asked why did he go all the way to Italy to buy a gun, and it's considered rare and expensive enough that when he loses it in the sea the Lloyds, with whom Dylan had insured it, recover it from the bottom of the sea rather than refund him.
- Battlefield 1 contains a large amount of rare historical World War I-era guns:
- One example that pushes this trope Up to Eleven is the Standschütze Hellriegel M1915, a drum-fed water-cooled submachine gun which never went beyond the experimental phase, had no known examples that survived the war (making it a rare gun so rare that it no longer exists), and the only evidence showing it are a few photos, all of which only show the weapon's right side. Worse, its documentation is so sparse that little is known on how it is operated, or who the name stands for. It's a miracle that it is even in the game at all. Not only that, but the few extant photos and documents indicate that it was actually a crew-served weapon, with the Hellriegel feeding ammunition from a chute on a drum.
- Another example of a weapon that is practically unique is the Maxim submachine gun, a submachine gun based on the MG 08/18. Only a single example that is known to still exist. Nobody knew who made it, how many were made, or even what its actual name was.
- Battlefield V follow suit:
- Just like how the previous featured a self-loading conversion of the Lee-Enfield rifle alongside the original weapon (BSA Howell Automatic Rifle), this game features another self-loading conversion, this one◊ made by Russell J. Turner.
- One of the many firearms in Hot Dogs, Horseshoes, and Hand Grenades is the French Union pistol. The pistol is a fully automatic variant of the Ruby pistol with a unique horseshoe magazine that can hold thirty-five rounds.
- Sniper Elite 4 features the ZH-29, one of the first successful semiautomatic rifles in history.
- Call of Duty: WWII features several examples, including the Fliegerfaust, a 9-barreled anti-aircraft rocket launcher that never left the prototype phase in real life.
- Call of Duty: Modern Warfare 3 and Call of Duty: Ghosts feature the FAD, a Peruvian-made prototype bullpup assault rifle, of which only 180 were built, and of which little is known - so little, in fact, that Modern Warfare 3 didn't even know how to animate loading a round into the chamber.