This is actually starting to become sorta funny. The commander's 50 is fired by electric cylanoids (spelling). There are no "butterfly" handles on it. The comander fires from inside the tank. Now I stopped being in an armor battalion, except for a 2 month period last year, so things might have changed but Tank Table6, 7 and 8 both have a 50 Engagement from a buttonned up position. That would be sorta hard if it weren't possible. You asked the question, got your answer, now you want to debate the answer. As far as firing an M4 from the hatch, Grun asnwered that question.
Bigsky...yep thats the original on display at the Patton Museum at Knox.