Sci-fi Weapons, Vehicles and Equipment

Okay... thanks for the help. Now, my understanding of this thing....

Basically, these article trying to illustrate the whole things like this: Normal computer bit was like card, you read it upside or downside, yes or no, 0 or 1, like that. The article said that quantum bit was like a bunch of stacked cards, with every card can represent different "yes" and "no", and you can only reviews one card at a time.

But, with my knowledge on how atomic structure and magnetism works (admittedly, that was about 16 years ago)....

The whole thing are start looking less like stacked deck of cards and more like Rubic cube.

So, what about infantry weapons that can use magnetic rails technology? Barrel of the rifle is a pair of magnetic metallic rails, with sliding contacts for an electrical current that passes through the projectile, creating a magnetic field to accelerate said projectile at hypersonic velocities.

The guns would be powered by Applied Phlebotinum.

So basically personal rail or coil guns? Soft sci-fi style?

Pretty much, yeah.

If the amount of amateur coil guns around youtube is an indication, we're probably going to get coil rifles before rail rifles.

What's the difference?

Angelus: Not necessarily true in that regard. Coil guns for the military seem to be looking more towards the low velocity projectiles like mortar rounds rather then small arms. Though you never know what the future might bring so why the hell not.

Tactical: Weapon designs, projectile designs, heat considerations, and power requirements to name a few.

Jasaiga: For our hypothetical personal EM weapons it all boils down to can we get the power source for it to be small enough and have enough acceleration behind a projectile to compete or surpass contemporary fire arms.

Lets start with a very rough approximation for a very rough of idea of what it might look like.

So we have a black box soft sci-fi power source and sorted out the material science side of the problem. For fun lets say we have a way to manage recoil up to 20mm Hispano Suiza and Soviet 14mm rounds as a standing shoulder fired weapon for big guns and .50 BMG for common infantry weapons.

Lets start with an AMAT weapon. The weight for the weapon is lets say arbitrarily as heavy as the Barret M82A2, about 30lbs, with the same partially over the shoulder stock design. Because it is just for a simple frame of reference and I think it looks kind of cool. Just about everything we know about the weapon is a black box design to simplify this.

This will be an AMAT weapon I will do a smaller caliber rifle next.

Ok we need to figure what it would take to possibly put the punch of those bigger bullets in terms of joules delivered into a smaller projectile.

Lets go with a 10mm diameter projectile and say it is half the weight of the heaviest .50 BMG rounds which puts it at a 400 Grain bullet.

We need a rough point of reference for our target energy to find out how fast this round needs to zip along to meet that estimated target energy. According to this NAVSEA DTIC article stumping for 20mm AMR's, the NTW-20 firing 20mm HS has a muzzle velocity of 2,600 FPS firing the M-95 20mm HS AP round. Said round, just the projectile itself, has a weight of .29 lbs/0.13 kg for just the round. Plug that into the Shooters Calculator for an estimate for impact energy and you get 40,836 joules. Lets say our target energy is about 40,000 joules. That is our target energy for our MANPACK EM AMAT (translated man/personnel portable/packable Electro Magnetic Anti-Material) Weapon from the projectile at the muzzle.

The EM AMAT would have a projectile profile very roughly like this.

So to get that 400 grain/.0259kg .39"/10mm projectile to hit that hard you need it to go about 5,800fps:1,767.84 m/s:1.767 km/s.

That is one zippy little round and has higher muzzle velocity then most modern large tube artillery pieces. It would have a very flat comparative trajectory at very long ranges and would likely kill or seriously damage just about anything short of a tank.

So taking that basic information and plugging it into another simple ballistic calculator with ballistic coefficient borrowed off of a similar weight high velocity round in this case the .408 Cheytac-claimed but for our case it works as we are not looking to be super accurate.

Here is your very rough ballistics chart. The projectile is still super sonic at 9,000 yds and potentially lethal well past that. You would have a huge MOA drift but guided projectiles could possibly solve that issue.

Now for the EM Semi-Auto AR pretty much all the same black box considerations as the other weapon only smaller and lighter.

So lets step it back for the personal fire arm. I am just going to halve the bullet weight and diameter so a 5mm projectile with a 200 g/.0129 kg weight.

Lets say we want this bad boy to hit as hard as the 800 grain Barnes .50 BMG which gives us target energy of about 20,000 joules.

So to make that smaller round hit about as hard as that .50 BMG round it needs to hit about 5,775 fps:1,760.22: 1.760 km/s. The reason the velocity is about the same is pretty much all the values are just halved. However those two estimated muzzle energies for the 20mm HS and the Barnes .50 BMG are pretty much exactly that.

For the sake of simplicity I am going just say it has the same BCE as the other round by design as calculating an actual BCE of a desired shape is a huge pain in the ass. You pretty much have the same ballistic chart only this round has obviously less energy at impact then its bigger AMAT cousin at the same ranges.

Here is the basic and fairly simple ballistic calculator I used. You can play with it and see what it does. It isn't the most accurate calculator but it is good enough for the back of napkin stuff like this. It has a basic trajectory calculator, recoil energy calculator, bullet kinetic energy calculator, and a max point blank range. Max PBR is distance from in which you do not have to adjust your sights for drop. firing at 16x16 (rough center mass target size) the EM AR rifle for example would have a max PBR of about 3,000yds/2.743 km. That is a really flat trajectory.

So there you go some very rough back of the napkin and with can of salt look at one possible consideration of personal EM weapons.

edited 15th Oct '16 8:46:47 AM by TuefelHundenIV

Holy shit. You'd literally need energy shields to protect against that. Unless we have something akin to Vibranium

Well I should note how effectively that energy is delivered will still heavily rely on round construction and composition as well as mass and velocity of said round. Those rounds even as a "ball" round though are going to be hitting really damn hard. Such soft rounds would do damage to a lot but they would spatter against any hard armor and heavy cover.

edited 15th Oct '16 9:18:26 AM by TuefelHundenIV

Maybe you just need another railgun to fire a slug to intercept that slug.

But then railguns would fire slugs just before the real slug to intercept your counter-slug which would require another counter-slug to counter the main slug behind the counter-counter-slug.

Slugception.

So you need a big heavily armored ship carrying a beast of a nuclear reactor to power the battery of railguns which it will fire in broadside to overwhelm the enemy's defenses. A BBRN perhaps?

Yes and each main gun is actually a 5 barreled Gatling railgun and there will be three of these per gun turret which would mean each gunhouse has...

...FIFTEEN BARRELS OF HELL!!

And I suppose we'll go with the now-standard 3x3 turret arrangement. The aft end could feature a helipad or maybe some VLS cells

Midship would feature VLS cells. Two racks of 96 missiles each. And the aft end would carry a flight deck for VTOL craft such as Harriers. All the gun turrets would be built towards the fore end.

Depending on how heavy the hangar facilities are, stacking three turrets fore could off-balance the ship. You could probably disperse some of the railgun defenses in smaller twin-mount turrets around the superstructure.

I'm not really sold on railguns, as opposed to missiles or simply kinetic mines. If you're going to have a huge power plant on board, you might as well power a laser with it.

You might use railguns as a deliver method for missiles, instead of the missile having to carry the whole fuel payload needed to accelerate to the target, it could just have the fuel needed for delta V maneuvers and course correction, relying on the Railgun to launch the missile with a high enough initial velocity.

Besides, lasers can't be arced which is a fairly hefty downside once a railgun starts shooting at you but you can't shoot back since it's on the wrong side of the horizion/planet.

But lasers make great point defenses, giving you a good chance to intercept that over the horizon round.

Plasma weapons would arguably make better ones, still short range and highly effective at vaporization, but unlike lasers, they can actualy stop a laser.

That would operate under the same limitations as smoke defenses do- ie the protection is short term and difficult to deploy on the move. Plus Im not certain a plasma weapon could vaporize an incoming munition quickly enough, at least withkut frying the person who fired it.

Assuming you fed it from your shipboard fusion reactor (is scifi after all) you could do a nasty number to any projectile that was incoming, solar plasma is nasty stuff, and considering you can hold it in the ship, you should be able to direct it just enough to keep from incinerating yourself.

Although I will agree it is much less practical for non-spaceship entities like tanks or powered assault armour.

Yeah, I meant my comments to apply to ground based combat.

Though, I do have to question what kinda power source you stuffed into a tank or powered assault armour for laser based point defences to be viable, that would be a large draw.