by artm on Mon Aug 24, 2015 4:51 am
They are perfectly fine for shipping containers provided you:
1. start with a pallet
2. lay down 4-inches of foam, same as used for cushions
3. lay down one box
4. lay down a sheet of 1/4-inch or 1/2-inch plywood
5. repeat with foam, box, plywood
6. strap it all down
7. shrink wrap it
This is perfectly safe for transport, seen it done three times myself. You can even use the foam and plywood sandwich to transport them in a vehicle (no pallet); I transported my Cal Sigs like that.
So, the boxes are useful to a new buyer or if you need to transport yours for repair - saves you some money from having "correct" shipping boxes shipped to and from you.