Uniform is ever about with the gun (9)
I believe the answer is:
equaliser
'the gun' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
'uniform is ever about' is the wordplay.
'uniform' becomes 'equal' (I've seen this in another clue).
'is ever about' becomes 'iser' (I can't explain this - if you can you should give a lot more credence to this answer).
'equal'+'iser'='EQUALISER'
'with' is the link.
Can you help me to learn more?
(Other definitions for equaliser that I've seen before include "reply that might make one point" , "One may demand extra time" , "Goal to tie" , "Levelling goal" , "weapon, perhaps" .)