Science Buddies: "Ask an Expert"

So i have been thinking, and looking at the physics of a railgun, and the speed the projectile moves, what would be the end result of two projectiles fire at each other and colliding, while flying at the speed of approx. Mock 7? A rail gun projectile is a metal rod, so with no warhead or form of gunpowder in the mix, would there still be an explosion caused by the intense heat created by the collision? I can imagine there would be a massive shockwave, but i am uncertain as to what the full end result would amount to.

Science Buddies is for students in grades K-12 who are doing science projects. There are other forums on the internet where you can discuss this. Thank you.