I'm not sure we can make it really 'cheap' while still getting enough destructive power at lower levels. I'm leaning more in the direction of
anti-batlesuit weapon rather than anti-infantry for the moment, since a good laser or mini PSL or gauss design probably fills anti infantry better/more efficient. Though plasma bullets does sound cool, I must admit.
Maybe as an alternative to the gauss rifle or as alternative gauss/ rocket rifle/sibilus ammo.
And let's assume for a second that the hardware price and reliability for a plasma weapon are the same as for a good laser (which is generous towards the plasma design I think, but why not). Since a laser also works through applying heat (which is also the primary damaging component of a plasma weapon) we can then compare how much damage/penetration power you get for the same amount of energy (eg same sized bluerad shard) and determine if the slightly different damage type of plasma weighs up.
If not, we can just use a laser with same energy use and be better of. The point is that we shouldn't go for a plasma weapon because plasma is cool and exotic, but because it gives good bang per buck (or at least acceptable bang per buck, so that it having a bit different 'damage type' could come into play).
The problem with just using a shell is that the shell will break apart on impact, and the plasma will just erupt into a fireball. With a toroid magnetic field holding the plasma in a ring, the plasma won't scatter until the core itself is destroyed, and by then it'll have deposited at least half of its plasma into the target - that's not even accounting for the plasma itself spinning in the toroid. The aerodynamic shell is then simply designed to break - it is neither expensive like the plasma-containing one, nor a good source of plasma-resistant materials to the enemy, it's just there to stop the plasma from scattering to the winds.
Well, you are right that it would explode into a plasma fireball if it were just a regular container.
But as I alluded to, the idea is that while traveling, the plasma is contained in a (foot)ball shape, and once the shell hits it
cracks in such a way that the magnetic field lines form a thin cone to push the plasma out in a jet stream. Kinda like how in a
regular bomb the explosion goes everywhere, but a shaped charge funnels it into a focused jet. I'm not sure if it's possible to construct the
(electro?)magnets in such a way that they'll create the correctly shaped field lines to concentrate the plasma and push it forward, but it
sounds much easier to build something like this than to get strong enough field lines to contain a plasma out of thin air (aka without an outer shell).
The shaped charge analogy is a rather apt one really, we could call it a 'shaped plasma charge' and it'd be pretty on the mark.
Here, I made some horrible drawings to illustrate the point. The lines show the magnetic containment lines, and thus how the plasma is shaped.
Note that after penetrating the armor, it might result in a spray of hot plasma everywhere depending on how far the field lines reach.
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Hmm. This is a tricky thing, ain't it? The shell is probably the best alternative, but I have a sneaking suspition that it's gonna be pretty expensive and probably not that different in effectiveness or price over all. It might be better over all to ignore this as a technological dead end and focus on other, more viable technologies.
Yeah, I'm getting this feeling as well. However, if you'll humor me, I'm gonna look into it a little more. but if it indeed doesn't work out, I'm gonna drop it like it's hot.
So, going with the design layed out above for a solid shell to carry the plasma, what price range are we looking at here? Assume that the plasma is formed inside the gun, and then 'injected' into the shell, which is then closed up (a sliding lid or whatever) and fired.
Secondly, regardless of delivery system, how does the raw destructive power per kilojoule energy used of a decent laser compare to that of a plasma weapon