Ways gunmen raised weapons (7)
I believe the answer is:
arsenal
'weapons' is the definition.
(I've seen this before)
'ways gunmen raised' is the wordplay.
'ways' becomes 'lanes' (lane is a kind of way).
'gunmen' becomes 'RA' (Royal Artillery).
'raised' says the letters should be written backwards (going up in a down clue).
'lanes'+'ra'='lanesra'
'lanesra' back-to-front is 'ARSENAL'.
(Other definitions for arsenal that I've seen before include "A military store of guns and armaments" , "Store of weaponry" , "Eleven" , "Where the guns are and who are The Gunners are" , "Football team - magazine" .)