Small arm aristocrat carries when leading riot (10)

I believe the answer is:
peashooter
'small arm' is the definition.
Both the answer and definition are singular nouns.
Maybe you can see a link between them that I don't see?
'aristocrat carries when leading riot' is the wordplay.
'aristocrat' becomes 'peer' (peer is a kind of aristocrat).
'carries' is an insertion indicator (inserted letters carried inside).
'when' becomes 'as' (eg 'when I walked' means 'as I walked').
'leading riot' becomes 'hoot' (I've seen this in another clue. I am not sure about the 'leading' bit.).
'as'+'hoot'='ashoot'
'peer' enclosing 'ashoot' is 'PEASHOOTER'.
Can you help me to learn more?
(Other definitions for peashooter that I've seen before include "Toy weapon" , "child's toy" , "Primitive weapon" , "Child's "gun"" .)
