During the trial scene, Winchester's uniform shows 3 brass buttons above his belt. When Hawkeye and B J show up with a picture of the guilty party, Winchester's uniform shows 2 brass, and 1 black plastic button above the belt.
When Charles, BJ, Hawkeye and Klinger are in a jeep to go to Klinger's court-martial, Charles is shown wearing the ribbon for the National Defense service medal. This award was not authorized until after the end of the Korean conflict so Charles should not be wearing it.
Winchester mentions J. Fred Muggs, referring to the chimp mascot from the Today Show on NBC-TV. J. Fred Muggs did not join the Today Show until January 28, 1953, after Winchester was already in Korea.