Originally posted by Tjay
As far as I know WWII tanks could not or did not shoot 'on the run' because of that reason. The Gyro-stabilised mounting hadn't yet been invented. You do see film of Russian tanks shooting during a headlong charge but I gather that was only at very dense targets and even then more a demoralising ploy rather than in the hope of doing any real damage to specific targets.
I can quote Huderian (my translation):
Shooting during movement, which was so popular at the peace time, at the war time was used only on special situations, for example at the suprise engagement, or in the night time engagements. Because stabilizing gear was not yet invented, accurasy was not high, and use of shells excessive.
About the soviet war time films, very often they were produced: for example I read a numerous accounts on how for chronicles many panzers and planes were send together, filmed, and then sent back to places of their locations. I saw couple such chronicles (it was a 20 frames long film from the war time films during the Soviet time, I saw it like 100 times

You could identify them by the low fighters flying over the tanks.
But, from the other hand, in the memories of one of the german panzer commander (he was in a tiger), who took part in Prohorovka battle, I read something like that: "t34 attacked us at
full speed, and because we had a problem with a gun, we could destroy it only when it came very close. While aproaching us it kept fire, and were able to fire 4 shells. After the fight I saw 4 marks from its shells on the front part of our turret". He said that to prove that t34/76 guns were uneffective against tigers, and german panzers loses to t34s were neglectable. May be that t34 was lucky, or that commander just forgot how it was, but that is what I read.