Audie Murphy was a short, scrawny kid who volunteered for the Army in World War II. He was undersized and didn't do well in boot camp, but he quickly made a name for himself and was promoted for his top-notch shooting skills.
When Murphy was deployed in France in 1944, his best friend was killed a German gun crew who pretended to surrender. He then killed the entire machine gun crew and then used that machine gun to take out all the other enemies in the area. Later in that same campaign, Murphy's company was pinned down by an overwhelming German force. He jumped into a burning tank wreckage (which was on the verge of exploding) and continuously fired its machine gun until the tide was turned. If that wasn't crazy enough, Murphy did all these things while suffering from Malaria.
A classic movie called "To Hell and Back" is based on Audie Murphy's autobiography and actually stars Murphy as himself. Surprisingly, he actually requested that certain parts be taken out because his insane story seemed so unbelievable.