Given the cone of shot, that might be good for very close in work on a vehicle (that has some protection from falling debris) but surely a much longer barrel, like the one in my video, would be better for more general use?
The longer barrel would give better reach, which is more use when a person is swinging it around because you can hit and damage things at greater distances, so you can start shooting before they get so close their explosive might hurt you anyway, but for this sort of stationary mount it is more likely to be defending a vehicle or position, and while it probably swings round quite quickly some FPVs will get very close before you get the muzzle pointed at them... so the longer barrel would be a disadvantage.
I have been rabbit hunting on the back of a light truck and a rabbit burst out of the bushes very close to the road we were driving down and one of the guys with a shotgun called it and casually leaned over the side and pointed the shotgun in the general direction of the rabbit and fired... and missed.
A long barrel shotgun with a choke might spread its pellets or shot over an area the size of your hand at 5 metres... the advantage of the longer barrel is that all the buckshot will be inside a 1m circle at 20m range.... which means 12-16 ball bearings similar to a light 9mm round randomly scattered over that area... against a human sized targets and you will get some hits.
For use against drones I would consider lighter shot like a number 3 shot which has about 120 pellets per shell so 120 small ball bearings in each shot spreading 1m across at about 20m increases your chances of multiple hits and they should still be moving fast enough to shatter propeller blades and damage plastic structures.
The lighter pellets offer better density of shot so it is not likely to get a kill, but the heavier buckshot loads reach further, but there are fewer projectiles and you can't control where those projectiles hit within the circle of striking projectiles.
I would probably go for a mix of number 3 shot and buckshot and fire multiple shots at each target. For use in trenches buckshot only.
One of the clear messages in this conflict is that the International Atomic Energy Agency exposes itself as it can't bring itself to broadcast who is shelling Europe's largest nuclear power plant.
This is at the core of the entire situation.. the IAEA is corrupt and controlled by the west and serves the western interests over human interests...
They should all be fired.
BRICS needs to create an alternative that is independent of any country.
The bottleneck of noncontact warfare is the availability of launch platforms and actionable intel, not the missiles themselves.
Having all the ammo in the world means little if you can't find targets, and with all the HATO support it seems the Orcs are not finding military targets or not reaching them, so instead they become the terrorist and hit civilian targets.