In the scene where the soldier sent the information from the train, and then they received it at headquarters, Master Sergeant O'Malley (Tom Sizemore) knocks on the door of the General. The General says, "What's up, Gunny." That term "Gunny" (Gunnery Sergeant) is generally associated with the Marine Corps not the Army. However, the term "Gunny" is actually used in the Army, not as a rank, but as a duty position. In U.S. Army Field Artillery Sections (equivalent to a Platoon in the rest of the Army), one of the Sergeants First Class (E7, equivalent to a Marine Corps Gunnery Sergeant) assigned to the section holds the duty position of "Gunnery Sergeant", which is frequently abbreviated as "Gunny" (the other Sergeant First Class in the section would be known as "Smoke"). This abbreviation in the Army is not widely known outside the Field Artillery community, but it is not exclusive to the Marine Corps. If the General had previously worked with Master Sergeant O'Malley in a Field Artillery Unit, it is very likely that he would remember O'Malley as "Gunny".
The German sub-machine guns, MP40, magazines only hold 32 rounds but the soldiers keep shooting without changing magazines.
Crista Schroeder was the name of Hitler's secretary. The secretary in the movie was named Schroeder.
In the opening scenes, the Germans were firing a WW1 model machine gun. Probably the Spandau 08 model.