I've gone through most of the--quite few surprisingly--steampunk questions and although one answered my question for how a steam powered arm may function, this arm has a lot of exceptions. I'm basically going to relay all the information I've collected and the ideas I have.
It would function like a normal human's arm, no additional power really. You aren't supposed to be punching or attacking with it. It's simply a prosthetic limb.
The steam power is actually a secondary power source, the first being chemicals and chemical reactions/reactants. (Referred to as "Chem-Tech" in the game.)
Before you think about the arm, think about a chemical/steam powered revolver. That's my main concern.
3 and 1/2.) There's a loading mechanism and (I guess wires/tubing?) that connect throughout the arm and loading mechanism. The revolver, when held, can be fastened or connected to it.
The revolver is not technically connected to the arm but IS connected to the loading mechanism that is attached to the arm--plus the arm acts as a power source (or just one giant wire from the power source).
2 things really, is a chemically powered pistol possible? How would the addition of steam affect the chemical power, if any?
How powerful could this actually be? You're technically not limited, considering Chem Tech is pretty fictional but chemical powered things aren't. So what would the limits be until it hurts the weapon and/or shooter.
Once you have a pretty good idea of how the gun would work, my last question is what it would be forced to look like. If tubing is required to flow through each chamber or something, how would the final product turn out? Keep in mind the revolver is 7 chambered.
How plausible is this:
6 shots are chambered, each bullet is propelled by chemical force. The bullets' power/inertia can be optionally controlled by a steam powered mechanism (the bullet can be adjusted to fly further/"charged"). Say the 7th shot is always ridiculous, (and for added complexity, the 7th bullet is chambered in the center of the weapon).
Traditionally the cylinder spins and 6/however many bullets are kept in their own cylinders, in this case it doesn't spin on an axis but instead is rotated from the side to allow room for tubing or something.) how powerful could the shot be without breaking the arm (thus the point of the arm, shock absorption.) and what chemicals would allow for that type of power?
I'm still researching so if I figure out any of the math/science myself, I'll add it in.
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Alright, I've read through all the recent comments (the last 4 or 5 days) and I've made a lot of changes. Firstly, I'd like to apologize for how vague the information is, it was pretty early in the morning and I hadn't really slept--I just took the opportunity when I saw it. Anyways:
A few things should be brought to light, most importantly "propelled by chemical force". Yes, I'm an idiot. I honestly didn't even think about the fact that normally bullets are propelled by chemical reactions--I completely understand the confusion behind that.
To elaborate, the "chemical force" ISN'T gunpowder. Although that would be much simpler, it's also boring. Unless there's a way for me to incorporate steam and the other chemicals/Chem-Tech. Basically the gun doesn't use gunpowder or at least not primarily. *(Actually, after writing everything below this, it's probably going to use gunpowder... simplicity is soothing.)
Alright so the next problem is that only a few people have realized the complexity in the "7th Shot". Not only is it's location kind of inconvenient, but also I still don't know how powerful it can actually be.
So my next step, naturally, is the chemical reactants you guys have to work with. I'm currently trying to ignore the steam powered portion of the weapon/arm just to make it easier. Once I think I have enough to give a semi-finished product, with everything combined, I'll pitch it to you guys.
New specifications:
Okay, Chem-Tech. You guys need a definition of sorts, but I can't really give you one. I've decided that Chem-Tech can simply be something infinite, and instead use gunpowder for the revolver. Chem-Tech is simply an unknown substance that makes up for any lack of power.
The steam is magical: Yes the steam is technically supposed to be some sort of infinite power source, created by magic. I'm trying to ignore that, but let's try to keep it in mind in case you find yourself saying "Oh wow, I don't think steam can do that, dang." It's just magical then, okay?
The arm is just as important as all the other components, it transfers most of the power and provides a lot of needed stability. Let's assume the arm is created from some sort of aluminum/iron mix or something. It might be slightly heavy, but whatever. Say they can lift, point, shoot, don't even bother factoring weight unless it's important for determining power. The arm is only meant to make things less-breakable, we wouldn't want someone to shoot this gun and loose a limb.
When you can, don't make things infinite. In the case of Chem-Tech, it's basically always infinite but we're not really using it to power the bullets most of the time so it's fine. It's just an additional fantasy element needed to clear things up.
Ammo is still a thing, I'd just go ahead and assume these are .44 caliber bullets. Make them as durable as you can--even infinitely durable, as it's kind of important our bullets don't disintegrate. Honestly this is more about the weapon than the ammunition it uses.
The super powerful, mechanically complex "Seventh Shot". Or... is it? So I know that steam power will limit the power of the shot a lot, adding gunpowder helps if I'm forced to, and the strength of Chem-Tech is unknown. I mean it could just become a seven cylinder revolver, and the user simply chooses to fire the 7th bullet at maximum power most of the time. Ignoring all of that, how would the seventh shot be incorporated so that it can deal maximum damage without damaging the user. Picture it like this:
We have 3 power sources, lets make gunpowder explosions, G; steam power, S; and Chem-Tech is C.
__ amounts of G create the force needed to propel a bullet.
__ amounts of S create additional force, that can be implied whenever needed. Let's say our character never misses, he can essentially add __ S and turn this revolver into a sniper rifle.
__ amounts of C. I can't even say how powerful C is, nor can I think of a reaction that is as controlled as gunpowder in the form of liquid chemicals. So let's just make C infinite, there is no limit. C simply makes up for all mishaps, it fuels the generator for the steam power maybe, it makes the gunpowder stronger if it isn't enough. It simply makes up for all loose ends--but it doesn't actually propel anything.
Now let's say we use C instead of G... say that C is controlled and can propel the bullet with infinite amounts of kinetic energy. Even if this is a controlled reaction, knock-back/recoil is still a factor. Despite our mechanical arms efforts, at what point would the weapon become unusable--the arm or weapon breaks. Keep in mind that the revolver is primarily made of iron.
So far that's what I've kind of re-thought about. It's difficult to compile all of this information. I've decided that I might actually write the story for the character and then talk to a few of you individually about it. This way you guys understand what the character seems to be capable of, and understand the limitations. This is also the first time I've had some legitimate difficulty writing a character. Normally I get this sort of science stuff sorted out before the character is written. In this case I need a bit of an example and I'd also like to construct a blue-print of sorts.
(There's a lot of you that deserve credit for correcting most of my mistakes, and giving me new ideas. Seeing as that's basically everyone, I'm just going to issue a thank you.)