How old is this!

Factory sealed 4# of Herco. Anyone have a idea on how old it is? Can is in excellent condition. Also have open can of Red dot and Alcan and open 1# cans of Unique and 2400. Bought them at a yard sale. Thanks Donnie

nice score, if you do use the powders keep the cans, there's some collectors out there.

Should be a lot/date/time stamp somewhere