Large number upset after US detective produces weapon (6)
I believe the answer is:
pistol
This might be a double definition.
'large number upset after us detective' is the first definition.
Although both the answer and definition are singular nouns, I can't see how they can define each other.
'weapon' is the second definition.
(pistol is a kind of weapon)
'produces' is the link.
Can you help me to learn more?
(Other definitions for pistol that I've seen before include "Rectangular" , "Hand weapon" , "Officer's side-arm" , "Small gun" , "Small firearm" .)