Weapon hunt (5)
I believe the answer is:
rifle
This clue is a double definition.
'weapon' is the first definition.
(I know that rifle is a type of firearm)
'hunt' is the second definition.
(to rifle through is to search or hunt through)
(Other definitions for rifle that I've seen before include "Ransack - firearm" , "Gun; plunder" , "Sack; firearm" , "Author of report" , "Shoulder firearm" .)