RAIL GUN! You beat the military into getting them into projectile-based operation!
Seriously, because the thingys are staggered, and it looks like a ball wouldn't fit down this barrel, IT IS

a rotary sweeper that will take the balls up from the BallAquisitionDevice to the Shooter inside a cylindrical canister.
Honestly, we thought about something like that for 2009 but we detiremened it wouldn't be effictive because of the large holes in the balls.
Hang on, were the Moon Rocks swiss-cheesed to save weight for the field prep crew?
