Check this out:
That’s seven layers of steel right there. And there are no explosives in the cartridge. It’s the fury of friction and velocity you’re seeing.
However, the rail gun is also huge, and it requires a traveling power plant that could otherwise generate enough electricity for 18,750 homes.
So it’ll mostly live on ships.
Here’s a video with more info:
As the technology improves, they hope to be able to steer the projectile with GPS.
But right now, they’re still working on finding a way for the electronics to withstand the G-forces.