Ah, yes...., we gave Bovington a big handfull of those old 4"(?) smoke discharger thinggies, fired using a No1 action. Loading was by hand, outside the tank but firing was by remote bowden cable from inside! Things haven't changed much because the 6 barrel multi directional smoke dischargers you still see on tanks are loaded from the outside but fired (electrically this time) from inside the old Centurions, Chieftains, Ferrets et al.

I often thought about putting in a spoof suggestion, suggesting that there ought to be a little door in the side armour of the turret where the loader might stick his hand outside to re-load the smoke dischargers. Something like a cat flap...............

I don't think I have ever seen those things used. A quick hose down with the co-ax Browning or a couple of rounds of cannister would usually be enough to quell the most restless wild colonials or antipodeans