Rifle and bow breaking that man's back (6)
I believe the answer is:
search
'rifle' is the definition.
(I know that rifle is a more specific form of the action search)
'bow breaking that man's back' is the wordplay.
'bow' becomes 'arc' (both can mean a curve).
'breaking' is an insertion indicator.
'that man's' becomes 'he's' ('he' refers to a man).
'back' says the letters should be written backwards.
'hes' reversed gives 'seh'.
'arc' inserted inside 'seh' is 'SEARCH'.
'and' acts as a link.
(Other definitions for search that I've seen before include "Forage, quest" , "Fish about" , "Scour, seek" , "investigation . . . ." , "Seek (out); hunt (for)" .)