Two thirds of soldiers in automobile as they take shots (7)
I believe the answer is:
cameras
'they take shots' is the definition.
(cameras take photographs)
'two thirds of soldiers in' is the wordplay.
'two thirds of' becomes 'cames' (I can't justify this - if you can you should believe this answer much more).
'soldiers' becomes 'ra' (abbreviation for Royal Artillery).
'in' means one lot of letters goes inside another.
'cames' enclosing 'ra' is 'CAMERAS'.
'automobile as' acts as a link.
I am not very happy about this link. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for cameras that I've seen before include "Light-proof boxes" , "Image recorders" , "television equipment" .)