Just thinking out loud, but maybe you could have custom made .2 bioBBs from BBB?
As if you're ordering a bunch for all games in the year, have the BBs colored, like it was said on the first page. If it's light blue, and you're the only field owner requiring light blue BBs, people can walk away with your BBs and as you know only .2 bioBBs are light blue, you don't have to worry. Do a mag check at the chrono, and if you see a white BB, you know who's cheating.
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