About a year ago, I was the guest of an official of a major university. Near his desk was a nicely mounted piece of one inch metal plate, about 10 inches square with a 5 inch hole blasted out of the middle. He said this was one plate out of a stack of a dozen or so that had been hit with an slug shot from one of their experimental electromagnetic cannons. He declined to give more details.
IIRC, they used to experiment with plastic slugs in these rail guns.
I am making a desk ornament for my son ....it is a test projectile slug that was fired from one of those EM rail guns - fired at NSWC Dahlgren in Virginia. He acquired the test slug when he was doing an internship as part of a “super Senior thesis project” while attending USNA. My son gave me the the slug when he completed the internship - but I figured I would make it into a nice desk ornament for him in the future. When completed, it will be a nice ornamental paper holder that is as intriquing as the metal plates with the hole in it!! (The slug is a small aluminum billet that weighs about 4 lbs....and has some interesting deformations. It was fired into a sand-pit to absorb/dissapate the kinetic energy.)
Rail guns sound great, but there are many big technology hurdles remain to be solved before a suitable rail gun will be put into operation! The “ALL ELECTRIC” ship basically means that your power generation is electric first, and then you have electric motors connected to the propellors (instead of the turbines - through reduction gears, driving the propellor.) The ship might be making flank bell - and then temporarily shift power from the shaft to the EM rail gun energy bank - it might take 10 seconds to charge the energy storage bank - then power is switched back to propulsion. [sounds very Trekkie - charge phasor banks, shift power from life support to shields ....etc.!!]