Guerrilla skilfully made top for percussion caps (8)
I believe the answer is:
partisan
'guerrilla' is the definition.
(similar in meaning)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for partisan that I've seen before include "Arts pain (anag.)" , "Enthusiast" , "Prejudiced in favour of a particular cause" , "of prejudiced views" , "champion" .)