This is a bugged / glitchy achievement as of December 9, 2021. (Fixed now!)
It SHOULD unlock after completing the ‘quest’ at Ransom Keep. For some, it popped fine. For others it won’t pop at all.
Will update solution if/ when a fix arises. Until then, keep try the other outposts, there are 7. Guide below:
Ransom Keep:First, you will have to complete the first 3 missions, Warship Gbrakkan, Foundation, and Outpost Tremonius. Head South-West (down and left) from your first FOB. Ransom keep should be marked on your map already, so you can set a waypoint by pressing
on it on the map if you want. From there, kill the enemies at the base and then press
to find the Silo controls. Use your reload button to open them and then shoot at them or throw grenades until they explode. There are 4 In total. There is also an optional Scorpion tank you can hijack in a building there. The Scorpion tank is a powerful tank that can help you destroy the silos and your enemies. Then, sabotage the vehicle repair bays. This is as easy as pressing reload on them again. Once you see fireworks, the achievement should unlock.
UPDATE: The achievements should be unlocking normally now, if you should have gotten this in the past either wait for it to pop or destroy another. Mine popped after about 5 minutes of gameplay on 12/9/21 (should have gotten it 12/8/21).
Many other achievements are exactly like this bug wise - waiting seems to do the trick