That's....that's really not unlikely. I shoot down enemy planes with the rear guns in bombers all the time.
I agree with you, but we are talking about a Stuka here. The rear gun is a single 7.92. The Stuka is probably the easiest bomber in the game to take down. Should have been easy prey for a Spit MK IX. I was thinking of how lucky I was so i decided to post about it.