I can't edit my post now, but to be clear I was talking about kinetic energy. I would have thought momentum is not a very useful thing to talk about in a case like this where there was some pretty obvious transformation of energy into damage, etc.
As I said though, I'm far from a physicist so happy to be schooled if I'm way off...
As I said though, I'm far from a physicist so happy to be schooled if I'm way off...