1. Select this location:
OLD RUSSIA, EARTH
EXPLORE COSMODROME
Old Russia, Earth
Key locations:
Cave near space ship.
Cave near helicopters.
Building near helicopters, conn-ex/container outside.
3. Killing enemies away from any of these locations should spawn a loot box when you go back.
4. You can do this back and fourth with any of the above locations, there is a 99% chance you will get a loot box there every time. The amount of loot was reduced from the beta but it still works.
5. This will help you get plenty of loot in order to purchase your latest unlocked items, especially the high valued ones. Loot boxes also contain special items. Good gaming.