I put them in cheapy ziplok style freezer bags a hundred rounds at a time and store the bags in ammo cans. Makes it easy to know how many I'm taking on that range trip and they take up zero room in the range bag once I've emptied them. I "label" each bag by dropping a post-it note in it with the load info.
My personal preference is to use the factory boxes in the cans; I don't reload, and, like one of the comments above, my OCD likes it better when I can easily count the rounds.