Another line of thought is to include a single-use battery per projectile, similar to a modern round incorporating ignitor and propellant (primer and powder). It doesn't matter that the battery is destroyed through the discharge.TLE2 wrote:IMHO, a portable rail gun is more likely than a "ray" weapon.
As battery technology advances, it may be able to get velocities comparable to firearms in a sufficiently small package to carry. I would expect rifle-sized weapons to appear first, or at least first after larger scale military weapons. Then as electromagnetic and battery technologies advance, pistol sized packages should appear.
And who's to say you couldn't tinker with them? Polish the "barrel", upgrade the magnetics, higher voltage system, etc.
Just remember that any sufficiently advanced technology appears to be magic... until you understand it.
Regarding tinkering- it's just another skill set. Your basic tool kit goes from a set of hand tools to a soldering iron and a radio shack catalog. Your top-of-the-line tool for an armorer goes from a metal lathe / mill to a PIC programmer and 3D metal printer.