_backpack = unitBackpack _unit; _backpackWH = "GroundWeaponHolder" createVehicle (position _unit); _backpackType = typeOf _backpack; _unit action ["DropBag", _backpackWH, _backpackType];
...does not work most of the time, and instead:
Action::Process - No target [action: DropBag]
...pops up in the RPT-file. It does work occasionally though (no idea why), but rather rarely.
The other action "PutBag" works fine, but then you don't have a pointer to the weapon holder - which is kind of handy, if you'd like to "AddBag" the backpack later on...