check it out 20:38 there is a shot where he puts the gun to his head and slowly pulls back the trigger, look close, there is no firing pin (the reason why when he opened up the chamber none of the bullets had strike marks on it) Either the pawn shop guy sold him a faulty gun or knew it was a faulty gun hoping he would just get caught and go to jail. Tom figured it out right away when he pointed it at him, then gave it back because he knew it would not work.

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Ted Striker: My orders came through. My squadron ships out tomorrow. We're bombing the storage depots at Daiquiri at 1800 hours. We're coming in from the north, below their radar.

Elaine Dickinson: When will you be back?

Ted Striker: I can't tell you that. It's classified.