Why would guns not work in the dungeon?

Question

In my setting I need to have a dungeon where people cannot use guns or other gunpowder weapons.

The reason can be anything: it's impossible to bring guns in, guns don't work inside the dungeon, using a gun is unsafe for the shooter, anything.

I originally thought about a flammable gas being released in the dungeon. But I'm not sure if gunshots can ignite gasses in the air, and if such gasses exist that would be breathable (I want no other side effects).

Is there any way a modern civilization could build such a dungeon?

**Edit- ** more details, as requested

The setting The setting is an extreme reality show. Contestants are put on an island and they try to get points that are hidden in dungeons scattered around. There are also native people on the island which can supply them with guns, which is why I don't want guns to be used inside the dungeons- the show runners want gory face-to-face combat in case two teams arrive at the same time.

I don't want to get into the nature of the natives in this post, so for the sake of the question assume they have modern level technology but are easily manipulated and don't exactly have free will. I'm still not sure about the number of natives there will be, but probably the population of a small city.

The dungeon The dungeon is built by an incredibly rich entertainment company for the reality show. They can be assumed to have almost unlimited resources. The technology level is like I said, near future. The company however cannot have employees physically on the island while the show is running, so the "no guns" rule should be enforced physically and not by some guard. I thought about having the natives guard the dungeons, but native guards can be bribed or killed. The dungeon should be able to last about 2 months. However maintenance visits are possible.

The purpose of the dungeons are to create tense conflict between contestants if they arrive at the same time (which is likely, because teaming with others is encouraged by the rules but so are betrayals). The system should also not allow older kind of guns. Weapons inside should mostly be things like spears, knives, bows, etc'. If the system can be cheated by a smart contestant that's fine, but it shouldn't be easy.

The people entering the dungeon The people who are supposed to enter the dungeon are the reality show contestants. There are 100 of them, and because of the natives, they are capable of manufacturing modern-day items.

They would have time to prepare but not as much as they want, because they will try to get to the dungeon first before other contestant teams. The natives will tell them what will happen if they use guns in the dungeon, but not why.

Answer 1

Forfeit

If this is a reality show, then there must be cameras (or something analogous). And it's in the interests of the show runners to get good footage of the event, so it should already be against the rules to destroy, circumvent or simply evade the cameras, because what's the point of any of it if they can't broadcast it happening?

Given that, it should be possible for staff on the mainland to monitor these cameras at all times. If they see anyone using firearms, then that's an immediate disqualification. They lose all their points and are no longer eligible to win. If they wanted to make the punishment even more severe, they could take away access to any resources that the other groups have: locking out their key cards, disabling any electronic devices they've been issued, even voiding their ticket back off the island.

Answer 2

Hopefully one of these helps:

• The dungeon air is 90% oxygen. Fires are catastrophically violent and explosive, and a gun will not function safely. Also, they fight harder because they get tired less quickly in the high-oxygen environment.
• The dungeon is contains large quantities of a hand-waved gas that reacts badly with gunshot residue. When you fire the gun, unburned traces of propellant are expelled into the air from the barrel. These vapors react with the gas in the dungeon to create a corrosive/explosive/poisonous cloud of death that severely hurts if not kills people near the gunshot.
• The dungeon is susceptible to cave-ins, which can happen if a bullet strikes the wall, or even with the noise of a gun going off.
• The contestants are hunting each other, and the dungeon is very, very quiet. Guns are loud and give away your position.
• Powerful magnetic fields in the dungeon pull on all metal objects, leaving them stuck to the walls. You can get ceramic knives and swords, but a gun made of anything other than metal will shatter on firing.
• There's a monster in the dungeon and you don't want to make loud noises. Alternatively, he can smell gunpowder.
• The cartridges available on the island are pretty cheap quality, and don't survive the damp conditions of the dungeon.
• The roof of the dungeon is made of crystal spikes that are sharp and heavy enough to kill you if they land on you. Make a loud noise and you'll bring down all the ones near you.
• The walls of the dungeon are part of an organic life-form with a defense mechanism. If you injure them with a stray bullet, they close in and crush everybody.
• The walls of the dungeon are part of a predatory life-form that eats animals moving through it. The contestants have to keep quiet lest the floor turn into digestive juices.

Answer 3

Given the setting is a show and somewhat higher tech and plenty of resources can be assumed of the organisers, I'd go for a relatively dumb solution that is also based on technology:

1. All guns have trackers. The organisers are supplying the guns to the local population and they have trackers or identifiers installed in them. It could be active GPS connected and stuff or just a passive RFID chip. What is important is...
2. The dungeons also have detectors for guns. Think the devices that they put near the exits in supermarkets:

Normally, if you walk through it with a non-deactivated/removed RFID chip on your purchases, it would start beeping.

Instead take them and just inverse their function: you walk through one before you enter. If no gun is detected then the dungeon door opens. If any gun is detected, then you can't get in until you leave it outside.

That's not too high tech - it's something we can do today. The biggest effort would be making sure all guns are fitted with RFID chips but given it's an island and the organisers are fairly wealthy and influential, that shouldn't be too big of a problem.

This solution could be scaled to be more futuristic if you wish. If the guns have transponders with GPS in them, then the organisers can track where each gun is and maybe enable/disable some facilities. So you could have people only be able to enter some place with a gun, perhaps. An even more futuristic version could have remote controlled guns where the organisers can disable the gun (jam it, perhaps?) remotely. So people can get guns inside a dungeon, but it won't fire.

Although the more high tech solutions require some sort of power drain from the tracking system, so you might have to deal with that. Yet, it can also work towards your advantage - if a gun can only fire if the tracking system is charged, then firearms are temporary. Once the batteries run out, they become useless. That's a great limited boon to toss in a game - it would motivate players to act before the time runs out, instead of hoarding the guns.

Answer 4

Actually, it is harder to reason why they're not use pneumatic guns

Pneumatic guns are almost as deadly but do not have most of disadvangates of guns listed here (i.e. there's no fire, no toxic gas, much smaller danger of ricochet and cave-in, they can be non-metallic).

I guess you will have to resort to screening. Anything looking like a barrel is not allowed.

Answer 5

Do you smell that?

Neither did the contestant last year who died in a fiery explosion when he lit his cigarette.

Coalbed methane

A real danger in our world and a cause of hundreds if not thousands of deaths in coal mines, even when guns are not involved.

While it is a toxic gas, it's not likely to kill you at levels at which it can explode when it meets fire or even a bigger spark from a ricocheting bullet (but yes, it technically can kill an unlucky contestant). It's also odorless and invisible. And worst of all - you don't know if it's there or not. Since it comes mostly from coal seams, it's not going to be everywhere in the dungeon and because it's lighter than air, it will always try to travel upwards through the corridors. You may pass a few hundred meters of methane-free zone just to walk into a corridor full of methane without noticing.

Simply make your dungeon from an abandoned coal mine and you get a perfectly viable, real world reason not to bring a gun unless you want to kill both your opponent and yourself.

Want the smart guy to abuse the rule? Bring a canary!

Canaries were used by miners to detect methane and other toxic gases - because of their anatomy, the bird would die at a much lower levels of methane in air than humans. Your pocket bird died? Get the hell out of there... or prepare a fiery trap.

Answer 6

The dungeon is surrounded by deep vacuum or water under tremendous pressure. This can be because it is located in outer space or on the bottom of the ocean or can be the result of creative engineering. Any use of firearms within the dungeon has the potential of puncturing its walls and killing everyone inside.

Answer 7

Sound restrictions ?

Maybe some heavy guardians will rush to your position if a gunshot is heard, which are a lot more terrifying than the rest of the creatures? some kind of zombi-like terror, if you are too noisy everything will rush on you, because the creator of the dungeon love to read in peace.

Tradition

Dungeons should be revered and getting in one is seen as a ritual. bringing a gun to the ritual is a blasphemy.

Echo

Walls are just reflecting so much sound, using guns is just ear shattering and no fun.

Speed hacking detection

any particle moving too quick is detected and this area of the dungeon considered defective, destroyed and regenerated automatically

Non Newtonian fluid

"it's not air we are breathing, it's handwavium gas, known to stop bullet as quickly as water do"

Etc..

Guns are are pretty distinct from other weapons, so you can pretty easily distinguish them, and ban the difference with the weapons you allow. Just don't forget that it can affect other stuff sometimes, like grenade explosion if handwavium gas, or communicating with teammates if sound is restricted

Answer 8

Black powder

These rifles can use black powder, which is composed of three ingredients - nitrate, charcoal, and sulfur. Now there are two reasons this can't work, the simple reason and the fun reason.

The simple reason is that black powder doesn't fire when wet. If these dungeons are incredibly damp places, you can't fire a black powder rifle. (Specifically matchlock and flintlock - and yes, those aren't modern day rifles, but they can be made using modern techniques like rifling to make them much more effective weapons.)

The more complex reason gets into chemistry. The proportions here could have as much as 30% sulfur. When black powder is discharged, it creates products - one of these being potassium sulfate. Now, I don't know any equations or found any of them out, but it's possible that the presence of potassium sulfate would react with some kind of mostly harmless gas already present in the cave to form, say, a compound like sulfur oxide. Which is a poisonous gas.

Answer 9

You don't need to make up a contrived premise that will lessen the verisimilitude of your story, just have it be It's illegal

The island's colonial ruler nation has strict gun laws that also apply to the island. Possessing a firearm requires licensing and training, which the contestants do not have. If the show depicts firearm use it will be taken off the air and the producers of the show will suffer legal consequences, so the producers are very assiduous about keeping them out of contestants' hands. They don't have to have a physical guard on the island, they have their money on the island. The island local government has signed a lucrative contract with the production company to host the show on the island and neither they nor the natives are going to let anything jeopardize it.

Answer 10

Other aspects of sound have been addressed but, assuming these dungeons are enclosed areas, what about the effect of firing a gun on one's hearing? In this case, the show runners and/or natives could tell the contestants directly that guns are not advisable.

Answer 11

Guns are mostly made of metal.

Place very strong electromagnets inside the walls of tue dungeon - the kind used in magnetic cranes. When those are on, carrying a gun will be a hazard: you may die from a gun pinning you against a wall and piercing through your flesh to get to the magnet.

Wooden weapons will be safe. It is quite possible to make a spear and even a knife with only wood. You can also make tips for spears and arrows using stones.

If you really want to be sadistic you can turn the dungeon into a giant induction oven. The magnets don't need to be as strong, but they must change polarity very fast, like a few hundreds or thousands of time per minute (super easy, that's how induction ovens work). Instead of pulling the guns with extreme force, the walls will cause any guns to heat up very fast. It takes a few seconds to make a piece of metal go way past 212F/100C.

In both cases guns could be damaged beyond use.

Answer 12

1). A specially bred species of wasps lives in many parts of the dungeon. They have the characteristic that if they smell gunpowder (or burnt gunpowder), they go to the area where it the smell came from and then viciously attack anyone in the room.

2). There is a fire detection system that will (purposely?) also detect gunshots. The doors to the room then close and lock, and the room get sprayed with lots of water. Extra fun if the room is flooded with (unbreathable) fire suppressant gas.

Answer 13

Smart guns

Conglomeratings, the company running the reality show isn't a stand-alone company. It's a part of a global conglomerate of companies in all types of industries.

One of those industries is firearms, where Gunglomerate has effectively become a global monopoly. And since this is in the (near) future, society's reached the point where smart guns are widespread.

Modern smart guns can identify their user, such that only their rightful owner can fire them. Gunglomerate's guns, however, also have sensors which detect radio frequencies which set areas as 'off limits', where they cannot be fired. This can be powered using old-school tech like what's used in crystal radios, which can be powered by the radio waves themselves.

So all Conglomeratings needs to do is put hidden antennas within the dungeons. People will arrive in the dungeon and notice their guns don't work (maybe the guns beep to indicate this or... maybe they don't, and the players are in for a surprise!), and then all bets are off.

If you're concerned about players disabling the sensors, that can be solved in two ways:

• either they're too wrapped into the gun's mechanism, so that to break the sensor is to break the firing pin;
• or reverse the process, so that radio waves indicate where guns can be fired. So the dungeons instead have radio frequency jammers (thereby disabling the guns), and to break the sensor is to disable the gun permanently.

Answer 14

What about if guns work just fine, but everyone on the island is just very much convinced that using guns in the dungeon is incredibly lethal to everyone involved (the user, anyone standing nearby and most likely the person shot)?

To convince the contestants have natives comment on it if they see the players with a gun. Maybe someone selling supplies who has set up shop near the dungeon entrance. If they see a contestant waving a gun around they leap up in surprise and fear and drag the character around the corner and show them the crumpled and destroyed ruins of an old entrance to the dungeon.

"This used to be the main way to get inside until someone went inside with a gun. We heard the explosion echoing all over the island, and since then, no more guns and only one way in. There were four of them testing themselves against the dungeon together and the only part we ever found was the gun, blackened and twisted. It's mounted on the wall above the bar in the local drinking hole in town."

You could even have some kind of trap inside near the other side of the destroyed section of dungeon to explain this, for example, a room with highly flammable gas that ignites if the trap goes off. The old party fought someone in here, the gas was ignited by the gunshot and boom.

Guns could be perfectly fine to use elsewhere in the dungeon, but the contestants don't know that, the company that runs the show warns contestants not to bring guns before they turn up and who's going to risk smuggling a gun on to the island just to possibly blow themselves and all their friends up.

Answer 15

Ammunition Constraints

If you design a dungeon with hundreds or thousands of beasts, which all need to be killed, nobody would consider using firearms, because they would run out of ammo. Nobody would be able to carry thousands and thousands of rounds on their person.

Answer 16

Fear of ricochet

Your dungeon is set up with many small rooms and passage ways. Any use of a gun would be in very close quarters. Even if you could be sure that your victim was not able to kick or grab you or the gun in any way, it's such a tight fit in there that all shooting would be at close range.

Bullets are more likely to ricochet off flat, hard surfaces such as concrete, rock or steel, but a ricochet can occur from irregular surfaces within heterogeneous materials including soil and vegetation. (ref)

The walls of the dungeon are all flat and hard and very prone to ricochet. In addition, many of them are curved.

The angle of departure, both vertically and horizontally, is difficult to calculate or predict due to the many variables involved, not the least of which is the deformation of the bullet caused by its impact with the surface it strikes. Probability of ricochet is highest from surfaces approximately parallel to the axis of bullet movement, and grazing ricochets typically depart the surface at a smaller angle than the angle of incidence (or approach). Probability of bullet penetration increases as the axis of bullet movement becomes perpendicular to the target surface; but penetration may create a depression or crater within which the bullet may ricochet more than once, possibly following the arc of the crater floor to depart the crater at a greater angle from the original surface than the angle of incidence.

With a curve, your angle of impact is basically impossible to calculate since you don't know where your bullet will hit (either from missing, firing a warning shot, or hitting your target and having the bullet or fragments of it hit the wall.

Ricochets can hit the shooter, though this is less likely than the other options.
Ricochets can hit people you've brought with you (or the jailer).
Ricochets can definitely hit other prisoners too, the ones chained up or otherwise sharing the tiny dungeon rooms with your victim.

Guns are not the right weapon for targeting individuals in close quarters shared with other people, particularly when all the walls are hard and flat and curved.

Answer 17

Since the dungeon is pretty high-tech, what is stopping you from having a guardian doorway?

Lets say that to enter the dungeon all players/teams have to solve a riddle or puzzle, but all those who bring firearms will have to solve another puzzle. They dont know that the puzzle only appears when they bring firearms.

The puzzle will request anything to make the weapons worthless. It might require them to hit a target enough times, where "enough" just means " when the last bullet is expended". Or they might have to pool all the gunpowder of their bullets to break something they otherwise couldnt break (through the pressure for example) or they might have to make a sacrifice by simply offering all their firearm weapons. Should the players come back later the puzzle is simply reset and they have to do it again.

You could perhaps leave the players/teams with a few shots, say 1 shot per player/team, if that makes things more interesting.

Answer 18

If they're in the dungeon for two months then a major factor would be how much attention you draw from other competitors. If you have a regular sword or whatever like everyone else has- you're worth no more attention than anyone else.

If however you bear a gun, something that not everyone has, you become a target; everyone wants that gun. So competitors generally decide not to take the guns because over two months they will almost certainly run out of ammunition but the attention they grab will be permanent.

Answer 19

The natives have given them blanks. Hee hee!

The natives are confederates of the show producers. Of course they are! They sold the adventurers guns and demonstrate they work, but all the ammo given to the adventurers are blanks, with fake bullet tips. The adventurers shoot the guns and make a lot of noise but no-one gets shot.

This makes for a great show. Someone thinks they are going to break the rules and be a big shot with a gun and then the gun does not hurt anyone. The person who thinks they are going to get shot cowers in fear. Then, on realizing the gun shoots blanks, they beat the bejeezus out of the shooter using the crap gun as a club. Ratings gold!

Answer 20

Fame

With reality TV shows, there is more money to be made from the fame than the show itself. Using guns is against the rules and guns are a weapon of the weak or cowardly. It would like being on "Survivor" and having Domino's deliver pizza to you.

The flamboyant and skillful fighters are the most popular and make huge money in appearance fees and interviews after the show. Gun fights in real life really aren't that TV worthy and tend to be over quickly.

The producers want ratings gold and the contestants want fame and money.

Answer 21

The technology setting is modern and the show runners have some level of control over the natives.

So, while the natives can provide guns, they can only provide guns that have a special detector built in that deactivates the gun the moment they enter a dungeon. The gun is built in such a way that it doesn't work at all without this device, so it can't simply be removed.

Answer 22

Since you are in the near future, just make all available guns having a radio receptor, if a specific frequency is received, the gun will simply lock and not fire. The dungeons have a radio emitter broadcasting that frequency inside, disabling all guns inside.

If you want a more gory outcome, instead of disabling, the radio frequency replace what the trigger of the gun does, and activate a explosive charge instead of firing, any fools trying to use the gun would blow his hand off instead.

(It also leave you a opening for a player gun-savvy enough to dismantle the gun and use the explosive charge in other way, or pushing the other team to use their guns inside the dungeon)

Answer 23

I am not a scientist, but there should be ways to heat specific materials with microwaves or ultra sonic waves and all these scientific stuff. So if there is a room at the entrances of the dungeon that does the following:

• Produces microwaves that would make metallic surfaces spark and gunpowder to explode.
• Produces sonic waves that will heat up flammable liquids such as gas (I found this that seems relevant)
• Releases electrical charges that would detonate plastic explosives.
• Discharges all battery related stuff for things like futuristic rail guns or lasers.
• Heats compressed air containers in case of air pressure weapons - Although these ones might have been quite entertaining.

Of course there are many ways to create a gun that doesn't need fuel to operate, like crossbows or spring operated weapons like a harpoon gun but those may add up to the fun as well.

Answer 24

1. Noise Level

Depending on the scale of your dungeon, a gunshot may or may not blow out your contestant's eardrums, and as such is a bad enough idea to avoid

2. Materials

If your dungeon is made out of something that bullets bounce off, then the ricochet could easily hit the firer, rendering guns useless except at short range, which meets the requirements for "bloody carnage."

3. Atmosphere

If the dungeon's atmosphere has volatile gas in the air, then if the concentration is between the Lower Explosive Limit and Upper Explosive Limit, then a gunshot would cause an explosion. Here's a link describing the phenomenon:

https://en.wikipedia.org/wiki/Flammability_limit

Answer 25

If you want a somewhat plausible science / sci-fi resolution to the scenario that cant be circumvented in any way then i have one here; TLDR at the end:

The Island is strange. Rumors have been circulating about such a place, where high technology items does not work at all. Then they found this island.. They say that if you take advanced equipment with you it.. just stops working. It breaks. Drills go hot, chainsaws melt together, old cars dont last a minute and the new fancy ones dont even start. And its not like some temporary interference. Whatever gets broken by the island stays broken once you leave. Humans and animals doesn't seem to be bothered by whatever it is. There have been a slight deviation from the norm in reports of nausea and headache from visitors, but new places often means new bugs and bacteria and excited investigation is not the best mood when it comes to remembering to hydrate properly in the heat.

When the island was first discovered it triggered a minor crisis in the global politics. The news of an undiscovered island in a place where it should have been noticed made everyone wonder. The chinese had navy nearby and would surely get there before the US navy. So the US sent airforce to recon. While passing near the island two of the jet fighters fell straight out of the sky, and ofcourse the US blamed the chinese. The chinese however rescued the crashed pilots and quickly decided to invite anyone who wanted to examine the island. And many did. The effect was clearly documented, even the satellite sent for orbital photography stopped working and became a useless floating piece of space junk when it passed through the column of space extending straight above the island. Still no one is sure what causes the effect, there were many attempts to examine it but the best ideas was often stifled by the islands mysterious effect. When researches tried to use different methods to measure IN to the effect from the outside, and by that also figuring out where the edge went, the best description they could give was that "its like, on the particle level, everything inside the edge is just a bit fuzzier". Theoretical physicists have also joined the fray and their latest theories talk alot about quantum fluctuations affecting particle volume. After a while with no certain answers and research going slowly the island falls in the shadow of other news that are making their way through the newsitem lifecycle.

Thats when the entertainment company sees the value in the isolated island. As everyone got access quickly and no nation could see any military value in an island where you couldnt even store supplies without risking them becoming worthless, no nation actually claimed the island. No laws apply. This made it perfect for them to set up their new extreme gameshow. Using a different combinations of high res cameras flying in circles outside the boundaries, mechanically triggered mirrors and some flintstone-tech level cameras for the hidden corners they have set up a perfect rig for viewing the action.

In the trailer a mean looking man with an air of military training about him describes how the island works. -"Stuff dont fit. It affects everything. Your favorite lighter might become impossible to close, or open. When our crew tried setting up a diesel generator the friction almost made it catch fire. The troops that got stationed on the island when it was newly discovered quickly learned that guns wasn't worth anything either. After two or three attempts at target practice they realized that the bullets wouldn't go through the barrel anymore, but the force that propels the bullet have to end up somewhere so you have to be lucky to not get hurt while firing in a scenario like that." The military man looks at someone off-screen and nods -"Sir, Does it have any effect on people?" Still looking at whoever spoke offscreen "well no documented dangers or anything like that. But one of my men is careful about his oral hygiene though, you know flossing and that kind of stuff. He keeps complaining that since we got here he cant get the damn floss in between his teeth" the man says with a chuckle. Then he turns more serious again and looks at the camera. "I'd tell you one effect it would have on people though. If anyone decided to war it out on this island they would be stuck without guns, tech or support from intel. We are talking close quarters combat with meele weapons. It would be back to the medival days. Whoever that wanted to fight for this place and have a chance to win, would have to become Savages"

TLDR; The area that includes the Island somehow changes tolerance levels of the roomspace itself, as if the smallest thing in the universe suddenly is a little bigger and everything that depends on it now becomes sliightly different, just enough to mess up anything with fine tolerances.

Answer 26

Underwater and lot of small gas filled rooms

Make substantial parts of the dungeon underwater (so gun range is just few meters and there is risk of destroing the gun) and diving equipment extremely cheap and easily obtainable. (Sponsored by company, diving equipement may be at price of longer kitchen knife maybe and stored by volumes in all native vilages.)

Then you can fill the rest of the dungeon with explosive mixture of gases, so shooting inside the dungeon means the room, where you are and few around just explode and if that does not kill you, it would damage your diving equipement and you have only small chance to get away alive at all. Not saying, that the gas CAN be poisionous/unhelthy/unbrethable - you have diving equipement so no problem with that under normal conditions.

It would make harpune, spear or trident much better weapon, than a gun - better range underwater, safe to use anywhere, much more interesting fights.

Also diving equipement affect the fighters in many ways - limited field of vision, heavy bombs with air, harder to fight efectively (so usual fight would last longer and be more attractive), alternative targets for fighters - you break his mask, rip his pipes from their place or something like that and run away - he now have other problems to solve, just to stay alive long enought to take and use spare equipement or somehow fix what is broken most.

Again bonus for dungeonmaster, as short fatal fight is nice, but short and eliminate victim forever. Slower more tactical fight, where you can make damage, which can be fixed at cost of time and material and leave enemy to his problem just to meet him on next floor again is better. And you do not want to fight to his death so much, as he is still able figt some time and make substantial damage to you - disable his ability to move fast and then retreat is better strategy, as if you can get to dungeon token before him and then leave, you had won this round.

Ofcourse if you can kill him in first attack, it is even better. But if you do not manage it fast, but you damege his equipement, it gives you big advatage, if you run away and search your profit rather, than his death (at risk, that you will die too).

Equipement being valuable target also offers much wider range of usefull weapons, like chains, tridents, spiked poles or many others, which are usually seen only in fantasy, anime or cheep kung-fu films.

Answer 27

Just make like reality and have guns be really loud like they are in reality. In indoor ranges, ear protection is very crucial even when everyone only uses pistol calibers of .45 or below precisely because of the loudness.

Have your contestants require hearing to compete and give them no ear protection or make it impractical to use ear protection. Maybe there are invisible creatures that give off a quiet, low tone that triggers active noise control in active ear protection and gets blocked by regular earplugs. Or just have the natives refuse to make anything with active noise control altogether and have that be the thing that tips the protagonists off against using firearms.