Murph's Thompson sub-machine gun appears to be made up of parts from both an M1928A1 and an M1 Thompson. The gun has a M1928A1 receiver and Cutts Compensator muzzle, but with an M1's "L"-type rear peep sight instead of the M1928A1's adjustable Lyman sight, and an M1's smooth barrel, which lacks the M1928A1's cooling fins.
This film was a success at the box office, earning MGM a profit of $1,095,000 according to studio records.
The American tanks in this film are M47 Patton tanks. They were produced post war.
NBC originally scheduled this film for broadcast on November 23, 1963. However it was canceled due to coverage of the death of President John F. Kennedy, and it wasn't broadcast until January 11, 1964.