Okay, this metal storm system, actually uses special 40mm
grenades, not off the shelf ones.
What it basically does is that it is supposed to intercept and
shred incoming RPG rounds, or anti-tank missiles before they can
hit the vehicle. Special 40mm rounds will detonate a certain
distance away from the vehicle in hope of forming a wall of lead to
shred the missile.
The entire system is computerised. Sensors that detect missile
launch will immediately slew the gun to the direction of the
launch, and fire the special 40mm grenades and detonate them at a
certain distance.
The system can also be over-ridden by the VC, to engage other
threats. Eg. Snipers in windows etc. Non-lethal rounds such as tear
gas rounds can also be fire from the same weapon without having to
change the rounds.
Eg, u see 4 firing tubes rite? 1 tube can be reserved for special
non-lethal grenades, while the rest can still pack other kinda
options, HE, etc.
About reloading. From what I understand from the current system.
THere is a small hatch under the 4 tubes. The 4 guns will point
upwards and move into a reload position, where the loader can
reload the weapon from inside the vehicle through the hatch.
The grenades are not individually loaded, but are loaded in forms
of magazine tubes. One tube would have about 4 grenades inside. So
its a matter of ejecting the empty tube, and putting in a new
one.
Of course an autoloader would be helpful! =D