Hi If you fire a Clark tank at another Clark tank you can hear bullets bouncing off . So if you traverse the turret firing the M.G. you will hear the bullets bouncing then fire the main gun.
I could see this being a problem for some clubs ,one more thing to check before battling can start. See if the M.G. is turned on, has it the correct load times and number of lives .May be they will start to ban the Clark board because they have to check more things and it all takes time.

regards pete