Last of machine gun's contents taken from sane soldier of legend (2,3)
I believe the answer is:
el cid
'soldier of legend' is the definition.
'el cid' can be an answer for 'soldier' (I have seen 'Spanish soldier' mean 'el cid' so perhaps 'soldier' could also mean 'el cid'). I'm not sure about the 'of legend' bit.
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for el cid that I've seen before include "11th century Spanish hero" , "Historic fighter" , "Rodrigo Diaz de Vivar was his original name" , "Ruy Diaz starts" , "Spanish soldier" .)