During the final battle scene where Tom Hanks' character is mortally wounded and, out of sheer, futile desperation, begins to fire his .45-calibre 1911A1 pistol at the tank that approaches:

o If you watch closely, as he fires shakily at the tank, the pistol's slide remains to the rear after one of the shots. This means he's fired all the ammunition in the clip. The scene changes.

o In the next scene seconds later, he's firing the .45 again.

The pistol magically reloaded itself!