Factual error: Raymond is equipped with what is described as a high-power Soviet sniper rifle. However, the rifle he uses is actually a Japanese carbine.
Factual error: The movie is set in the mid 1950s, as established by the cars and 48-star American flag cake seen at the party scene. However, the convention hall at Madison Square Garden has 50-star American flags hanging from the ceiling.
Factual error: In the scene when the Senator and Raymond's mother are in the hotel room, the newspaper headline (upside down in the lower right) states that he will address the Senate that day. However, in the next scene when he proclaims there are 57 Communists (based on the Heinz ketchup), there is an uproar in the chamber and he yells "Point of order, Mr. Speaker." The Speaker (of the House) is not in the Senate, he is the head of the House of Representatives.
Deliberate mistake: In Raymond's flashback to "when he was once loved" there is a scene where he is having dinner with the Senator and his daughter. Evidently someone didn't feel that this scene was quite long enough as shot. Raymond picks up a piece of meat on his fork, puts it in his mouth and then begins to laugh. Then he puts the empty fork back into his mouth, removes the piece of meat and replaces it onto his plate. Obviously, the film was reversed briefly to give the illusion of a longer scene.
Audio problem: At the end of the movie when the helicopter is flying into the area where the army team was held, the radio transmissions you hear are not aircraft pilots or controllers. You are listening to railroad dispatchers and trackside detectors.
Continuity mistake: As an unconscious member of the captured American patrol is being carried on a stretcher to a Russian helicopter, his helmet falls off the stretcher onto the ground. In the very next shot, the soldier's helmet is now not only on his head, it is tightly strapped to his chin.
Other mistake: When Raymond shoots Senator Jordan, his first shot penetrates the carton of milk that Jordan is holding in his left hand. From Raymond's perspective, that carton of milk is positioned over Jordan's upper left arm; so, the first shot should have merely wounded Jordan in the left bicep, hardly a mortal wound. But Jordan's eyes roll up and he collapses as if shot in the heart.
Character mistake: During the press conference the Secretary of Defense yells at Senator Iselin "Where is the Sergeant-at-Arms? Throw that man of out here!" The problem is that "Sergeant-at-Arms" is a congressional post and that is not a position that would exist at the Defense Department (the Pentagon), nor would the Secretary of Defense hold a press conference in the Capitol (where someone who has that title would be).