I am no expert... here is my two cents worth. It appears the blade was backed by wood (like a 2X4) and shot with a rifle round (due to the kinetics and caliber, I think a 1911 would ding or shatter the blade before penetration... too big - too slow). It definitely appears to have been done deliberately (not due to combat... its too clean). I hope I did not spend more than my two cents.
