Use of weapon when body enters fray (5,4)
I believe the answer is:
rifle shot
'use of weapon' is the definition.
(shot from a rifle)
'body enters fray' is the wordplay.
'body' becomes 'flesh' (flesh can mean the body as opposed to the soul).
'enters' is an insertion indicator.
'fray' becomes 'riot' (both can mean a disturbance).
'flesh' placed inside 'riot' is 'RIFLE-SHOT'.
'when' is the link.
(Other definitions for rifle shot that I've seen before include "Bullet" , "Act of sniper" , "report" , "Feature of war" .)