MTM Case guard makes an incredible amount ammo storgae boxes and systems that lock into each other, stack right and handle the weight effortlessly.
If I do not have ammo in the MTM boxes they are in the old .30 and .50cal ammo cans stacked in the corner of the gun room. MTM makes a tray to stack the old metal cans and they lock in good.
https://smile.amazon.com/MTM-AC4C-Am...0732133&sr=8-1