I had a big, big smile on my face when I thought of this. This is one of those Free-For-All game types where you CAN'T just sit around, waiting for someone to come to you. It's very simple, you take everyone's weapons away, put all of the loaners in a big pile, and have everyone stand at an equal distance away from it. The Herald calls "Lay On!" and the Free-For-All begins. Be sure to enforce the weaponless contact rules, such as grappling and body checks before starting the round as to make sure To determine equal distance from the center, just make everyone stand in a circle, have a herald hold a rope from the center, and another guy walk around the circle holding the rope at a certain point. Have people stand where the rope ends, and they'll all be at an equal distance away.
That was the 'Hunger Games' version. If you want a more 'Dodgeball-like' playing style, split everyone up into two teams, and lay the weapons in a straight line inbetween the two teams, with both of them standing equal distances away. This will reduce the amount of ONE PERSON being able to puppy guard the weapons pile, but at the same time will allow the team with the higher amount of runners to get more weapons.
And just because we're on the topic, I might as well suggest a 'Dodgeball' game, but played with Javvies. Why not?