Continuity mistake: When Klinger is coming over the hill at the end of the episode, the camera shows him in the outdoor setting, and the spot he's on has sparse vegetation. When the camera goes to a close up of him, the trees and shrubs are thicker and closer to him. This alternates a couple of times.
Other mistake: When Trapper and Hawkeye make the right turn after Trapper tries to use the restroom, you see that Trapper avoids the left side of the road just after the turn. This is to avoid the explosive charge set in the ground used to simulate a mortar round exploding.
Audio problem: In the Post-Op ward, Jimmy is playing poker with the two jerks in his platoon. After the cards are dealt, he sees that their deck has pictures of nude women. He looks up at them when seeing this, and you hear him say "Very funny!", but his lips don't move.
Continuity mistake: When the boys are working on the vascular clamp, Charles brings out three hard boiled eggs. After he heckles BJ and Hawkeye for a minute, BJ takes the hammer, and smashes Charles' eggs. The camera cuts to the boys, and back to Charles. There are now two eggs, and almost intact.
Audio problem: When the bulb in the projector goes out, Klinger is trying to fix it. People throw popcorn at him, saying "Find it!" After Potter says "Hit it, Father!", watch Klinger. From the wide shot to the close up, you hear him say "The bulb is hot!", but his lips don't move.