After picking flowers and putting them around his hat Kinnian is killed. As his helmet rolls off the flowers are already wilted, yet when Lt Benson gives the helmet to another soldier they are fresh again.
During the climatic battle, a group of American soldiers rush the foot of the hill an you can see a batch of enemy grenades rolling down the hill almost right upon them. When they cut to a close up the enemy at the top of the hill, they are just now taking the batch of grenades out for the first time and letting them roll down the hill towards the Americans.
Although the G.I.'s in the film are soldiers of the U.S. Army's 24th Infantry and 1st Cavalry Divisions, many wear Marine Corps cloth camouflage covers and World War II-type camouflage nets on their helmets.
When Lt Benson and his platoon reach a spot that is under heavy enemy artillery fire, Benson halts his men. He then takes out a pocket notebook and, over an extended period of time, calls out the names of his men alphabetically and instructs them to run through the shelled area to the other side during shelling pauses. In actual combat, a leader would never take the time to consult a name list for such a maneuver. In addition, Benson should have known the names of his men by heart without having to use the book.
At the beginning, when Aldo Ray points the Thompson Submachine Gun at Ryan the bolt is in the forward position. Since the Thompson fires from an open bolt, that means it was not cocked so it would not have fired. Ryan was in no danger.
Lt Benson asks one of his troops to wake him at 0500 (5:00 a.m.). But when Benson arises at that time, the sun is shining brightly. The shallow shadows indicate the actual time is probably mid-morning or mid-afternoon.