KINETICS IN SCI-FI | Why do guns keep showing up in science fiction?

Generic greetings and welcome to another episode of science insanity. Today an opinion piece on a sci-fi classic, kinetic weapons. Everything from cannons to railguns, flak rounds and PDC’s. We’ll break down the general type of guns you see pop up in science fiction and what they're good at. Then we’ll discuss why guns are so common and what they offer to the audience and writers.

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[tomc.]

Gunnery Chief:
This, recruits, is a 20-kilo ferrous slug. Feel the weight. Every five seconds, the main gun of an Everest-class dreadnought accelerates one to 1.3 percent of light speed. It impacts with the force of a 38-kiloton bomb. That is three times the yield of the city-buster dropped on Hiroshima back on Earth. That means Sir Isaac Newton is the deadliest son-of-a-b*tch in space. Now! Serviceman Burnside! What is Newton's First Law?

Serviceman Burnside:
Sir! An object in motion stays in motion, sir!

Gunnery Chief:
No credit for partial answers, maggot!

Serviceman Burnside:
Sir! Unless acted on by an outside force, sir!

Gunnery Chief:
Damn straight! I dare to assume you ignorant jackasses know that space is empty. Once you fire this hunk of metal, it keeps going till it hits something. That can be a ship, or the planet behind that ship. It might go off into deep space and hit somebody else in ten thousand years. If you pull the trigger on this, you are ruining someone's day, somewhere and sometime. That is why you check your damn targets! That is why you wait for the computer to give you a damn firing solution! That is why, Serviceman Chung, we do not "eyeball it!" This is a weapon of mass destruction. You are not a cowboy shooting from the hip!

Serviceman Chung:
Sir, yes sir!

[camerongunn]

As a Army infantryman I was both a machine gunner and a Bradley Gunner at times. I can assure you that flinging lead at your enemy is full of middle finger energy. Hard-on inducing energy.

[VickyAmaru]

One of my absolute favorite tropes in science-fiction is people still using the M2 Browning hundreds if not thousands of years in the future. Shoutout to Brigador, which specifically brings attention to this in its weapon description.

[vodamiinurl]

I like how Battletech handles ballistic weapons. They trade the higher heat of energy weapons for ammo dependency.

[rhodes]

The Expanse solves the recoil proble really well.
If you look closely at the martian PDCs you can see a small rocket engine firing out of the back of them. They have a built in recoil compensation rocket engine.
And with the railguns they are usually mounted on warships massive enough to not be affected by the recoil or they are built in a way so that the ship's main engine automatically fires every time the railgun is used.

[chengarqordath]

I think with kinetic weapons it's also often a matter of aesthetics and how "realistic" they want things to come across. Reboot Galactica and The Expanse were definitely going for a much more grounded grim and gritty mood than something like Star Wars or Star Trek, and part of that was using more "realistic" weapons than bright colorful lasers beams.

I also really liked how Halo used the UNSC relying or kinetic weapons while the Covenant used energy weapons, to highlight how the Covenant had more advanced technology.

[carboneagle]

A practical reason for not using high energy weapons in space scifi is heat management (which is frequently neglected). Getting rid of heat in a vaccume is difficult and flying around mid combat with huge radiators deployed sound like a good way to break them. Lower energy requirements -> less heat generated -> better combat stamina before cooking your crew alive.

[My_initials_are_O.G.cuz_I_am]

Gunpowder does have oxidizer, so does nitrocellulose (smokeless powder) and so does cordite, all common gun propellants have included oxidizers, because in the chamber and barrel of a gun the access to atmospheric oxygen is practically none, especially with the very short combustion times available.

[VallornDeathblade]

Well, when you need to fight the replicators sometimes propelling small pieces of metal via a tiny exposition in a toob is a better option than fancy plasma weapons.

[jorvoyte]

One cool thing about kinetics or missiles is that you only have a limited amount of them and need places to store it. Logistics can add a good amount of realism to a setting and make ships less do everything types to specialized warships.

[jonathonspears]

"Sir Isaac Newton is the deadliest son of gun in space"

The most effective weapon in space is a fast moving rock. Just ask Earth how it liked stealthy asteroids being hurled at it, or what the dinosaurs thought about it.

[Myuutsuu]

It is relatively easy to shield something against heat. Laser weapons are nothing but heat.
Shielding something against kinetic energy is actually quite harder.

[someonenoone]

The meta angle on including kinetic weapons in military sci-fi (of varying hardness) is a fascinating one. A standard slug or an HE shell is understandable for the general audience, one thing punches a hole in thing, and the other explodes in its face with sharpel. But then you can really scratch the proverbial technobabble itch with various colorful and cool descriptions. A guided HEAT shell, a gigantic uranium spike, the holy canister of flak. It kind of manages to satisfy both the casual part of the audience and the hardcore military science enjoyers. To various degrees depending on execution but still.
And yes, guns are simply cool as hell.

[nibblitman]

I mean physics just kind of works no matter what so Kinetics will just kind of keep working.

[Yellowjack]

The Expanse's guns don't push their ships back because the gun turrets themselves have thrusters behind them to compensate for the recoil (the thrusters ignite whenever the guns shoots). Battlestar Galactica guns may have a system to compensate recoil too.

[Amoschp]

It would be nice if Scifi shows lean more into the limited ammo aspect of using kinetic weapons because usually the most well known ships seem to have endless supply unless plot demands the heroes be nerfed to give the villains a minor victory.

[GoranXII]

Guns are simple, both to understand, and to engineer. They can also be much more robust, have a _theoretically_ unlimited range (the round will travel until it hits something, which energy weapons will lose energy or cohesion with distance), and depending on size can be loaded with a variety of rounds. It's also imaginable to have different types of projectiles on the same vessel, big coil/rail-guns for anti-ship work, and chemical-projectiles for point-defence work.

[grimm]

So fun fact if you are a fan of the expanse, the point you made about recoil for mass accelerators in that show is addressed in the cgi,

Eg: when roci shoots pdc's their is a burst or discharge behind the pdc same goes for the railgun

[Verdis_deMosays]

I like the way the Eve Online universe handled it: 2 races developed magnetic accelerator guns, one developed lasers, and the 4th...guns. Just plain guns. Why? Well that race were slaves fighting against an enslaving empire, so bullets go is simpler and easier to produce by the resistance. Fits the universe and still gives the rule of cool as your 1400mm artillery cannons go off and one shot someone dumb enough to sit still.

[larsmurdochkalsta]

A railgun making contact with armor won't just punch a hole. It's gonna cause substantial frag and spalling on the other side which will bonk a lot of soft tissue and cause plenty of respiratory issues as well as damaging unarmored systems.