This video of the Navy's new toy has been floating around for a while. Which makes it not at all less spectacular:

But if it's a railgun then what causes the not un-intimidating fireball of awesomeness?

One big question this video begs is, what causes the giant fireball? Rail guns are supposed to be powered solely by electricity, and don't use explosives of any kind for propellant. Babb told PopSci the answer: The flames are from pieces of the projectile disintegrating; the 7-pound slug is jammed so firmly between the rails that when it’s fired, pieces shear off and ignite in the air. There’s been some speculation online that the flames come from some sort of gas that’s been used to increase conductivity. Wrong: The EMRG uses no secondary propellant - just electricity.

They shear off, you see, and ignite in the air. That's what they do.

References:
* Navy's Record-Breaking Railgun Shot [noahmax6000 / YouTube]
* Navy Tests 32-Megajoule Railgun [Pop Sci]

Previously:
* Thursday Military Tech - The IDF's Tavor Assault Rifle
* Thursday Military Tech - The Totally Awesome Israeli Jets Of Operation Orchard
* Thursday Military Tech - Zionist Robo-Snipers