How could I make a point scoring system on Halo Reach?

I have build a basic game that I am using as a prototype for future projects, but I need a system that can be triggered by the ball falling on something, I have tried using explosives to push a flag and a bomb (from assault) onto their capture points, but that has not worked, if anyone has any ideas and/or a working system that I could borrow I would be very grateful, my Xbox live gamertag is eddy564