I understand the concept of leaving it in the original container, however the original container is awkward to work with and does not reseal well. Also, I do not like to haul the bulk container to range where I make up charges (too much chance for contamination). I believe I will use the ammo cans until I have sufficient 2.5 gallon shot shell powder cans to hold the BP. For trips to the range, I will use recycled 1 lb powder cans. When I repackage the powder I take a picture of the label and print it out as a label. It's cheap, accurate and easy to do. A fifty cent label keeps me from throwing away "unknown powders".
Again, many thanks for the good ideas.