That was interesting...recall seeing it. But the smoke happens after the gun fires and the gun is back in battery. Normally is caused by a new round being slammed into the breech or when the air pressure equalises and the bore evacuator releases the fumes it had sucked up. I'm looking at a puff of air/CO2 near the muzzle as the gun fires to kick up dust as always happens. (unless you are sitting in a foot of mud or snow)
Pattoncommander , do you have a video link that would show that effect ???
I was wondering if the air/CO2 has to come from the gun muzzle or if we could cheat by using some sort of rotary nozzle positioned underneath the tank chassis ????