Say, depleted TRISO fuel pellets are basically depleted uranium pellets, yes? If so, would they make a decent way to add weight to railgun ammo? I mean, depleted uranium has occasionally been used for when one wants a projectile with high weight, density, stopping power, and penetration, so it'd make sense that it'd be even more lethal when fired at railgun speeds. That is, of course, assuming that depleted uranium operates much like aluminium with respect to magnetic fields which, I believe, is why aluminium slugs are typically used in real-world railgun experiments.