IF, IF, I said IF you are going to use them in a timely fashion (otherwise why bother), what would be wrong in directly charging the prepped cases? Perhaps cap each case with a plastic plug for spill-free transport (upright in a loading block or cartridge box)? Just a thought.
Plastic plugs similar to this:
http://www.fastenal.com/web/products...x?sku=11130524
ETA: Darn! Serf'rett beat me to it while I was on the phone.