Peace on Us - S7-E2
Continuity mistake: When Hawkeye, Charles, and BJ are in the Swamp, Hawkeye starts his roll about being sick of green, and by the time he heads outside and talks to Margaret the blood splatter on his surgical gown changes.
Peace on Us - S7-E2
Continuity mistake: As Hawkeye storms out of the Swamp, he leaves Charles, Potter, and BJ behind. After the angle changes, you can see there is nobody in the tent, and the still is missing.
Answer: Even an Army field hospital would have SOME weapons for self-defense if the enemy attacked. What's meant is that it's not a combat outfit, and therefore wouldn't have enough weapons to actually attack anyone. (It's also mentioned a few times that the Officer of the Watch is supposed to carry a pistol at all times, but Hawkeye refuses to do it when he's in charge and Colonels Blake and Potter don't enforce the rule).
Captain Defenestrator