Years ago a weapons system was experimented: a gas- powered launch platform. This was scrapped because it was not deemed precise enough, as it was difficult to get the mix of gasses correct, thus messing with trajectories.
The other technology is in current development: electromagnetic launching. It is well within experimental stages, as huge rooms are used to store the energy used, among other impracticalities.
Why not combine the two technologies? Our sensor technology is precise enough to detect slight variations in velocity even at high speeds.
Sensors within the platform will allow for the detection of velocity variances, and using this information, electromagnetic forces can be used to either speed up, or slow down the projectile, correcting the total force applied.
Refining a system like this could provide more flexible delivery platforms, being able to use different gasses/mixtures, and using a widely varying range of explosive forces (small forces for very short distances, instead of facing your trajectory almost straight up, subjecting your projectiles to wind forces).-- twitch, Dec 28 2012 I like it.
Afraid that somehow they might be physically incompatible but don't rule it out. I am pretty sure a rail gun would not be usable for this, but a coil gun ought to work, assuming the barrel does not heat enough to fry the insulation on the wires.-- Kansan101, Dec 28 2012 random, halfbakery