Revealing mistake: Through the whole show, the submachine guns (Thompson's, MP40's, etc.) do not eject spent cartridges after being fired.
The Rat Patrol (1966)
1 revealing mistake in show generally - chronological order
Starring: Christopher George, Eric Braeden, Gary Raymond, Lawrence P. Casey
Revealing mistake: It is obvious a dummy was used for the scene of the lighthouse keeper falling to his death.
Sgt. Sam Troy: Let's shake it.
Trivia: The actor playing Hauptmann Dietrich was born as Hans Gudegast. He later changed his name to Eric Braeden.