Chap concealing new note about revolutionary weapons (7)
I believe the answer is:
gunnery
'chap concealing new note about revolutionary weapons' is the definition.
I can't tell whether this definition defines the answer.
'chap concealing new note' is the wordplay.
'chap' becomes 'Guy'.
'concealing' indicates putting letters inside.
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'note' becomes 'ner' (I can't explain this - if you can you should give a lot more credence to this answer).
'n'+'ner'='nner'
'guy' enclosing 'nner' is 'GUNNERY'.
Can you help me to learn more?
(Other definitions for gunnery that I've seen before include "Artilleryman's skill" , "(Use of) heavy weapons systems" , "Use of heavy artillery" .)