Rail Gun (of the non-Peasant variety)

[industrious]

So I'm playing this gnome wizard tinkerer, and came up with a (mostly) non-magical idea for a rail gun. I'd start out with a light crossbow(to fool my DM initially and to provide a base to mount it). I'd then forge a metal tube, with the interior wrapped in a coil of silver wire(Craft DC roughly 25), and the two leads would be attached to the end of a wand of shocking grasp, which would replace the crossbow trigger. To activate, load tube with crossbow bolt head, and activate the wand. Would this be allowed? And what kind of damage would it deal? It's hardly a game breaker, but I'm at a low enough level that it could be somewhat devestating.

[Indon]

Creating a functioning railgun would require very fine craftsmanship of the barrel - I'd probably require more than DC25 for the item to account for the required quality.

Also, when a railgun fires, the barrel becomes superheated. Silver would most assuredly melt, and the crossbow would probably catch fire. I'd allow it, and I'd let it deal pretty good damage compared to a crossbow (probably 2d6, and another d6 fire damage), but it'd be expensive and probably not worth it without the sophisticated technology required to actually maintain a real rail gun.

Edit: Also, the bolts would be more expensive since they'd need to be iron (I believe the standard is wood).

[Blackjackg]

I probably wouldn't allow it, if only because incorporating pseudo-science into D&D unbalances everything. Not that the crossbow is terribly bad, but it opens the door for all sorts of craziness. I'd say just suck it up and use a refluffed +1 shocking light crossbow.

[Hnefi]

In real life, the voltage discharged from a Shocking Grasp might be enough to propel a tiny metal object weighing a few grams to a velocity approximately equal to a pea shot from a homemade blowgun. In damage terms, you'd be better off with a BB gun.

In the game, only your DM can say. However, do you even know whether electromagnetic inductance exists in your game world - and does your character?

[MickJay]

Depends on your DM. One of the reasons nobody makes such things IRL (military, electricity-powered railguns) is that they simply wouldn't work, or wouldn't work nearly as well as a gun (or a real crossbow, for that matter). In best case, the bolt would be provided enough force to fall out of the tube, possibly hitting you in the foot, but all things considered, you'd just waste a charge from the wand. I mean, you can hardly expect to deal more damage at range with that bolt than with the device you want to power it with (and the device itself was already made to deliver the damage; there's the necessary loss of energy on the way).

I'd classify this as a cool idea which is just too impractical to use. I guess that if you used a 10d6 lightning bolt to power the gun, you'd shoot a bolt that could deal 2d6, possibly 3d6 damage at most.

[Random832]

So I'm playing this gnome wizard tinkerer, and came up with a (mostly) non-magical idea for a rail gun. I'd start out with a light crossbow(to fool my DM initially and to provide a base to mount it). I'd then forge a metal tube, with the interior wrapped in a coil of silver wire(Craft DC roughly 25), and the two leads would be attached to the end of a wand of shocking grasp, which would replace the crossbow trigger. To activate, load tube with crossbow bolt head, and activate the wand. Would this be allowed? And what kind of damage would it deal? It's hardly a game breaker, but I'm at a low enough level that it could be somewhat devestating.

Any plan that starts with "fool my DM initially" is not a good plan - at any point he can say "that doesn't work".

Your wand only has 50 charges, and I wouldn't give it more than 3d4 damage or so - and I'd also give it a very crappy attack roll unless you meet a higher craft DC than you can manage at a level below where you can afford a Wand of CL5 Magic Missile anyway.

No reason it shouldn't work, but nothing like this is described in RAW so it's purely up to your DM - easiest counter is "Shocking Grasp doesn't work that way"

Oh, and [pedant]that's technically a coilgun. For which you really need to be able to energize several different coils in turn. A railgun needs specially designed projectiles and is subject to wearing out and overheating. (on the plus side, it's probably worth higher damage than your coilgun idea)

The other problem is as others have mentioned, to make either design work effectively, you need a lot more current than CL1 Shocking Grasp can give you.

[Mr.Moron]

Wouldn't a use activated item of Launch Item be better for this sort of thing? It'd be 1,000gp and be able to launch any small object at high/damaging speeds.

[quick_comment]

Making a railgun is probably a DC80 craft check, and thats after the appropriate research.

And every shot requires a DC 50 reflex save on the part of the weapon or it takes as much damage as the target.

[PairO'Dice Lost]

Wouldn't a use activated item of Launch Item be better for this sort of thing? It'd be 1,000gp and be able to launch any small object at high/damaging speeds.

A coilgun or railgun would probably require a custom-researched higher-level version of it, but I agree that using a variation on launch item is probably the best approach.

[Shinizak]

what do you mean "of the non-peasent variety"

[Prime32]

I came up with an idea for a coilgun for this Eberron party which had a crazy-powerful airship.

Basically, you buy a lightning rail carriage or two, then convert them into a heavily reinforced tube lined with conductor stones. Have a permanent gust of wind blowing through this tube, at as high a strength as you can get. On one end put a custom magical location which can give objects the properties of a conductor stone for 1 round. Place an adamantium sphere inside, sit back and watch.

what do you mean "of the non-peasent variety"

A large enough group of commoners who take readied actions can pass a quarterstaff around the world in the time it takes to perform a single action.

[Mr.Moron]

what do you mean "of the non-peasent variety"

Because the system puts no limit of the number of people in an initiative countdown,and no limit on the total number of actions taken (just the number of actions any one creature takes). You can line up an arbitrarily high number of peasants next to each other, have them pass an item down the line. By the time it reaches the end it has traveled that distance in the space of one round: 6 seconds. Simply do the math and you have the objects speed at the end. Have real-world physics take at the point the last peasant releases the item, and there you have it.

[ZeroNumerous]

what do you mean "of the non-peasent variety"

Commoner railgun reference.

[Heliomance]

But why would real-world physics take over when the last one lets go? It simply does 1d6 damage at the end with a 5ft range increment, a -4 non-proficiency penalty and another -4 penalty for throwing something not designed as a thrown weapon. Not really worth it.

[Mr.Moron]

But why would real-world physics take over when the last one lets go?

Two Reasons:

1) Nobody likes Catgirls.
2) That's just how silly D&D thought experiments like that work.

[Random832]

Because the system puts no limit of the number of people in an initiative countdown,and no limit on the total number of actions taken (just the number of actions any one creature takes). You can line up an arbitrarily high number of peasants next to each other, have them pass an item down the line.

As Readied actions - that's the important part - without that, you have to line them up in initiative order, which will take forever.

[olentu]

As Readied actions - that's the important part - without that, you have to line them up in initiative order, which will take forever.

Well you could just have them delay.

[AstralFire]

But why would real-world physics take over when the last one lets go? It simply does 1d6 damage at the end with a 5ft range increment, a -4 non-proficiency penalty and another -4 penalty for throwing something not designed as a thrown weapon. Not really worth it.

Because silly D&D thought experiments often hinge upon selective adherence to rules of the world versus rules of physics in order to achieve optimal funny.

[kc0bbq]

I love how the world gets all googly-eyed at the word "railgun". They're not all that special except in really large scale with massive, massive amounts of electricity.

[PairO'Dice Lost]

I love how the world gets all googly-eyed at the word "railgun". They're not all that special except in really large scale with massive, massive amounts of electricity.

Because when people hear "railgun" they automatically think of the really large scale ones with massive, massive amounts of electricity.

[AstralFire]

I love how the world gets all googly-eyed at the word "railgun". They're not all that special except in really large scale with massive, massive amounts of electricity.

Massive, massive amounts of electricity, fire, or light always make everything better.

Wild West with swords? Blah.
Pump up the guns with fire, the swords with light, and give some old woman the ability to shoot electricity and HOT DAMN, you've got a worldwide franchise.

[The Rose Dragon]

Massive, massive amounts of electricity, fire, or light always make everything better.

Wild West with swords? Blah.
Pump up the guns with fire, the swords with light, and give some old woman the ability to shoot electricity and HOT DAMN, you've got a worldwide franchise.

I'm afraid I don't get the reference.

[AstralFire]

I'm afraid I don't get the reference.

Blasters and Lightsabers and Force Lightning, oh my.

[The Rose Dragon]

Blasters and Lightsabers and Force Lightning, oh my.

You said old woman. Palpatine only threw lightning when played by a man.

[AstralFire]

You said old woman. Palpatine only threw lightning when played by a man.

Yeah, I know. I was just trying to be as silly as possible.

[Lamech]

Shocking grasp gets a bonus against people wearing metal armour. It totally ignores the normal rules for conductivity as normally a giant suit of metal would be a faraday cage and protect the person some. In fact pretty much all DnD magic generated lighting ignore normal conductivity rules.

Which means its up to the DM. I would say no, this does not work, if you were playing a D20 modern game. If you were playing a DnD game I would say, no using science. Otherwise people start nuking stuff with major creation, and everything goes to hell.

[AstralFire]

Shocking grasp gets a bonus against people wearing metal armour. It totally ignores the normal rules for conductivity as normally a giant suit of metal would be a faraday cage and protect the person some. In fact pretty much all DnD magic generated lighting ignore normal conductivity rules.

Which means its up to the DM. I would say no, this does not work, if you were playing a D20 modern game. If you were playing a DnD game I would say, no using science. Otherwise people start nuking stuff with major creation, and everything goes to hell.

Wouldn't a suit of armor's design make the fact that it's a faraday cage unimportant, as you've now got superhot metal right on your skin? The only issue with it is that it should change to fire damage.

[Lamech]

Wouldn't a suit of armor's design make the fact that it's a faraday cage unimportant, as you've now got superhot metal right on your skin? The only issue with it is that it should change to fire damage.

It would depend on how much grounded out and how conductive the metal was. I don't know enough about electricity and killing people with it when compared to cooking someone in a suit of armour. The point is normal rules are ignored, even in a case where metal is specifically mentioned. If there was no mention of metal one could argue the game can't include every case, but here metal is included.

[Fixer]

Wouldn't a suit of armor's design make the fact that it's a faraday cage unimportant, as you've now got superhot metal right on your skin? The only issue with it is that it should change to fire damage.

No idiot would wear any sort of metal armor DIRECTLY AGAINST THE SKIN. It would cause severe chaffing. This is the unfortunate reason why chainmail bikinis could never catch on. *sigh*

Most often chain and plate are worn over cloth, perhaps padding, to cushion the blows from bludgeoning weapons as well as they protect against slashing weapons.

[DragoonWraith]

Wouldn't a suit of armor's design make the fact that it's a faraday cage unimportant, as you've now got superhot metal right on your skin? The only issue with it is that it should change to fire damage.

The more conductive it is, the less hot it's going to get. Conductance = 1/Resistance, the power of the electricity is P = V * I = I² * R = I² / G (conductance is G), so higher G means lower P.