During the first fight scene just before you see Gege accidentally shoot his friend, Fritz goes off with another German to look for Russians. However, as he sets off you can see that he has no bullets in his gun at all! There is no magazine attached.
In the English subtitles, the German troops are addressed as "Storm Troopers." The correct title of these men were "Sturmpionieren" or "Assault Engineers", who were highly trained in street fighting using flamethrowers, explosives, and other specialized equipment.