Sci-fi Weapons, Vehicles and Equipment

Theoretically a gauss rifle would be quiet, but the projectile would be quite loud and as Imca pointed out the power systems would make a bit of noise. It would be a hum/buzz noise, like power lines or a big capacitor bank. Depending on the power being used this could either be very quiet or very loud.

DARPA built a 45 stage gauss mortar capable of velocities much higher than a conventional mortar, and it was quite loud. The homebrew gauss guns you see online range from almost completely quiet to moderately loud depending on the design, though those are usually 5-10 stage.

Silencing a supersonic projectile is impossible by definition.

Well, the advantage of a Rail or Gauss weapon would lie with the tuning capability of the weapon.

You could set the weapon to fire a slower subsonic projectile or have a fully powered hypersonic shell flying in the same platform.

But surely, you'd need to get a shell design that wouldn't suffer too much from being fired at lower velocities.

Maybe if you want something quiet but packing a lot of punch, I'd think that having a low velocity first stage Gauss or railgun firing at subsonic speeds and the projectile being a gyrojet that would start accelerating after leaving the barrel would be a solution of sorts.

It will be expensive tho and have some downsides like the shell being more prone towards drifting before the rockets kick in or having poor energy at closer ranges.

Speaking of stealthy artillery, there's always pneumatic guns or steam catapults. The USS Vesuvius served as a sort of stealth cruiser during the Spanish-American War by using her pneumatic guns to lob nitroglycerin projectiles at Spanish positions. The first sound they'd hear was usually the shell going off when it hit the ground.

Which was handy, because it had a max range of something like 4,000 yards if they only partially loaded it with explosives, so the ship had to sneak in under cover of darkness and sneak back out afterwards.

Edited by AFP on Aug 9th 2018 at 4:04:45 AM

It still relies on projectile speed, my target rifle which was a .17 air rifle still had a cracking report because of the sheer speed it shot that thing at.

It wasn't like loud enough you needed ear protection, but you still knew it had went off.

I would imagine scaled up to war weapon proprtions it would have been even louder

Edited by Imca on Aug 9th 2018 at 3:37:17 AM

You could maybe suppress the shots if you can capture that blast of high velocity heated air in some sort of system of baffles and/or wipes.

You could go extremely low tech with a mechanical system like a trebuchet.

I don't know why you'd want to do that but it would be quieter.

You could always fire these weapons in space. Then again, Space Is Noisy.

DIY: You can fire a cannon or morter from inside a giant potato.

There are such things as artillery suppressors but not exactly something that is practical for a battlefield.

For suppressed effects on something on the scale of a personal weapon, you need a way to control the flow of the hot high-velocity gas typically by allowing it to flow into cavities where it expands and cools and loses velocity followed by reducing projectile velocity to sub-sonic to eliminate the supersonic crack. Even then the action of the weapon in motion is audible. I found a few videos a ways back where a sub-sonic suppressed shot is pretty much that, silent, but the sound of the action and the obvious thud of the bullet hitting something were audible. You can partly address the action issue by reducing the amount the parts move, such as bolt actions or self-locking actions that lock into place automatically after every shot.

Edited by TuefelHundenIV on Aug 9th 2018 at 9:46:36 AM

A weapon can be made as silent as the wind, but remember how noisy the wind can be.

It's like stealth in space. Nothing is actually silent, it just vibrates the air a little less.

The chattering sound MAC-10s made with their original suppressor is actually because of that. The MAC-10 has a pretty loud action, and the suppressor made the gunshot quiet enough for that action to be heard distinctly.

A quick writing question for everyone here. How often do you explain how the technology works in your settings?

That's something I've noticed with scifi, that sometimes people feel the need to explain how it works, when really they shouldn't need to often.

Like I've got all forms of fantastical inventions and ideas, but nobody really needs to explain the stuff, because usually the people who can explain figure everyone already knows, or the people just don't care.

A laser weapon is just another gun after all, you aim, pull the trigger, done.

I rarely explain how it works in the writing. That’s not something that comes up naturally in conversation often, or needs to be explained to the audience in great detail.

That said, I don’t leave the technology as a black box. I’ll figure out how everything works and create a worldbuilding sheet, so that technology acts in consistent ways, and if it does come up or need explaining it can be explained.

Edited by archonspeaks on Aug 10th 2018 at 11:21:44 AM

Most authors do it in expository dialogue or simply as part of the prose in third person omniscient.

Since I love worldbuiilding details either doesn’t bother me.

I use my setting for both role playing and a video-game, so I do the same as above because it helps with the game, and make a consistant behavior among things that should be consistent....

And well, when it comes to RP it also helps with idle chatter.

Partly crossposted from the military thread.

From June of this year. The inevitable blending of missile and gun based technology continues at a fairly steady pace.

Nammo is looking to put out a 155mm Ramjet projectile.

Edited by TuefelHundenIV on Aug 10th 2018 at 5:49:09 AM

One of my favorite things in sci-fi is when the narrator just plain refuses to explain it, with some in-universe justification, like Johnny Rico declining to talk down to the reader who of course knows all about how the technology works, or Captain Ky Vatta, who truly knows nothing about the technology in question, and doesn't want to distract her specialized crewmen by asking them stupid questions about something they won't let her touch anyways (in that case, even they don't understand certain key aspects of it due to in-universe copyright/trade secret/legal stuff, and certain components just have to be yanked out and swapped wholesale with new replacements).

And then there's Old Man's War, where the smartest guy in the group shrugs and states that he doesn't "have the math" to understand it properly, let alone explain it to a layman. By the second book, the same character does in fact have the math for it, but explains to the protagonist that the math gets really weird.

So, I've been wondering, if they're could be some "cheats" around moons and solar objects will less than ideal gravity? Like I think one Troper here basically said that his/her terraforming was basically "Fuck you, it's magic," in that terraforming could increase or decrease gravity...(somehow) and that would take care of that.

Was wondering if theres a more...elegant solution. Maybe build entire communities where the roads and buildings are 1G? and outside of that the planet/moon has its natural gravity? Or bury artificial gravity plates deep within the crust affecting the whole planet?

Spacedock actually covers that idea with some math about rotating habs.

I like the idea of 1G cities...

You'd have some serious engineering challenges and I can't imagine what kind of security you'd need to work around the artificial gravity plates

Turns out mathematically, it's possible to make a rotating gravity hab on the moon.

Really? How?

Spacedock has the answers, it might be inaccurate, I'm not a scientist.

Ha! Sure you could do it, if you rotate horizontally. I actually considered suggesting that, as a joke. Can you imagine building an entire city that way? Doesnt seem practical.