Sort of weapon taken from NCO was carried by everyone (5-4)

'sort of weapon taken' is the definition.
I can't tell whether this defines the answer.

'nco was carried by everyone' is the wordplay.
'nco' becomes 'sm' (abbreviation for sergeant major, a type of NCO).
'was carried' becomes 'bore' (I can't justify this - if you can you should believe this answer much more).
'by' means one lot of letters go next to another.
'everyone' becomes 'all' (all people).
'bore' put after 'all' is 'allbore'.
'sm'+'allbore'='SMALL-BORE'

'from' acts as a link.