Goofs

The stock archival footage showing the positions of the Communist troops that are being shelled alternate between flat farmland and mountainous country.

When Sgt. Zack opens the new box of cigars the dead soldier had been carrying, the cigar he removes is only half length with a charred end.

The stock footage used in the artillery barrage of the North Korean attack includes WWII-era footage of German artillery on the Atlantic Wall.

Short Round sings the South Korean National Anthem to the tune of "Auld Lang Syne" while Pvt. Bronte plays on his organ. However, the music to South Korea's national anthem was changed from Auld Lang Syne to the Finale of Korea Fantasiaat at a ceremony celebrating the founding of South Korea on August 15th, 1948, exactly three years after liberation from Japanese rule, and three years before The Steel Helmet was made.

During the sniper fight in the forest, Sgt. Zack dislodges a piece of fake shrubbery, revealing the wood planks that anchor the shrubbery.

Toward the end of the film as the N. Koreans are attacking the temple, several views show water-cooled machine guns (identified by the large jackets around their barrels) aimed and firing at the attackers, presumably by the American soldiers in the temple. However, the interior views in the temple show that the Americans are only firing air cooled machine guns at the attackers, and these guns lack the large jacket seen around the barrels of the water-cooled guns shown in the exterior views. (One water cooled machine gun is seen when Joe is nervously looking at the Buddha.)

(at around 1 min) Sgt. Zack shoots a door in the temple but no holes appear in the door. In a subsequent scene he does the same thing to another door but this time there are holes in the door,

When Short Round enters the dark temple and lights two candles, the entire ground floor is illuminated.

The enemy soldiers in the first charge that are killed in the first wave aren't there when the second wave charges likely because they'e the same extras.

When Zack first encounters Lt Driscoll's patrol, he admonishes them for being noisy and not knowing the proper way to conduct a patrol. He then goes on to be every bit as noisy as they were.

The LT of the patrol at the end of the movie called Zack 'SGT', though he never identified himself by name and rank, and his uniform had no rank.