"(You die, lose heavy ammo because of the perk that makes you able to carry more heavy ammo)"
Its in the first line and the perk is just called 'Heavy Weapon Ammo"
If you die while wearing armor with the perk "Heavy Weapon Ammo" (which makes you able to carry more heavy ammo) you will lose 1 sometimes 2 rockets even thought you havent fired your heavy weapon.
You are wearing boots with that perk on your hunter and a chest with the perk on your titan, not sure if you're trolling ヽ༼ຈل͜ຈ༽ノ