Audio problem: In Blake's office, he's talking to Hildebrandt about Klinger, and the camera does a close up on Blake. You hear him say "Of course", and his mouth is moving a little, but not forming the words.
Audio problem: As Radar sets the clock back to 4:30, you hear ticking. The clock is electric, and wouldn't make a noise like that.
Audio problem: Toward the end, after it's determined that Radar isn't the baby's father, there is a vehicle horn honking. When the camera shot goes outside, the sound of the horn is a few notes higher that when heard inside.
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