Other mistake: As Burns, driving the tank, runs over the Swamp, there's no sign of the still anywhere.
Other mistake: While playing golf, something blows up Henry's golf ball. When the camera does a closeup on Henry's ball, you can see that it isn't a golf ball, but a prop designed to blow up.
Other mistake: As Hawkeye sings in the Swamp to mock Frank, watch Trapper. He's miming the words until his cue to join in.
Factual error: When BJ opens the first box of tongue depressors the tongue depressors are packaged in a plastic bag inside the cardboard box, my research says that plastic bags were not available in the early 1950's. (00:08:06)
Continuity mistake: In this episode, as they come from the pad, Hawkeye told them to get his canvas tub. But in "None Like It Hot", he had one that caused a lot of trouble and they traded it away for ice cream.
Suggested correction: There is no reason he couldn't have gotten another one.
Other mistake: Many times during the series, soldiers are around the OR carrying a loaded weapon (magazine attached for example), when there is a sign outside the entrance that says "all weapons must be cleared before entering the building" or similar.
Suggested correction: With the rampant rule breaking seen in the show, why would this be a mistake?
Yessir, That's Our Baby - S8-E15
Plot hole: Charles has the money and family connections. Why didn't he try to get the baby girl sent to the US? Trapper and his wife almost adopted a seemingly orphaned Korean boy in an early episode, so it couldn't have been impossible.
Suggested correction: There is a difference between adopting a child and merely sending it to the States without any support system to be put into an orphanage.
Plot hole: This episode revolves around the doctors trying to "transfer" a north Korean surgeon to the outfit. To this end, they get him papers, uniform, dog tags, etc. In the end, the plot is toppled and The Korean Surgeon taken to a POW camp by the MP. In reality, it would not have ended quite so pleasantly. A combatant wearing the uniform of an enemy is usually automatically considered a spy, and Hawkeye, BJ and Radar would also have been considered guilty of espionage or at least complicity therein.
The Abduction of Margaret Houlihan - S5-E6
Other mistake: As Frank cocks his gun in the Swamp, the slide locks open and he has to hit the slide release to get it to move forward. Next he fiddles with the hammer. Next we hear the shot go off. Burns' excuse later is that he was cleaning The Gun and it went off (although admittedly, Frank doesn't always stick to the truth that religiously in situations like that). The slide on a semi-automatic locks open only if the magazine is empty or missing. The Gun locking open is also a clear, unmistakable indication that the breech is empty. He would have to insert a filled mag, then pull the slide back again to chamber a round before The Gun even had the chance to go off. One never does that while cleaning a gun. One does what Frank did to begin with: Pull the slide back without a magazine inserted to make sure the breech is empty.
Suggested correction: Frank has demonstrated on numerous occasions that he does not follow the rules of safe gun handling, so ascribing his failure to do so is not a mistake.
You are missing the point. His gun is demonstrably unloaded when we last see it. He would either have to change his mind about cleaning it and load it instead, or load it first and then try to clean it (which makes even less sense), neither of which is not supported by anything in the dialogue.
