My experience with DJI drones is that once you put anything on them, the tuning of their flight controllers leads to substantially worse flight times, stability, and overall safety.
I know the Mini 3 can carry a naked GoPro without struggling too much, so a mavic might be able to carry a couple hundred grams with decent performance. But the flight characteristics go out the window pretty quickly, so I suspect you couldn’t carry much explosives on these things.
I have no idea how much is needed. Maybe a small amount is fine.
does it have to be accurate? if you want to just use it for suppressing fire, i bet it's pretty effective. it's probably effective as a psychological deterrent too.
I know the Mini 3 can carry a naked GoPro without struggling too much, so a mavic might be able to carry a couple hundred grams with decent performance. But the flight characteristics go out the window pretty quickly, so I suspect you couldn’t carry much explosives on these things.
I have no idea how much is needed. Maybe a small amount is fine.