Great times for the gunners, in certain ways (4)
I believe the answer is:
eras
'great times' is the definition.
(I've seen this in another clue)
'gunners in certain ways' is the wordplay.
'gunners' becomes 'RA' (Royal Artillery).
'in' is an insertion indicator.
'certain ways' becomes 'es' (east and south - two directions. I am not sure about the 'certain' bit.).
'ra' inserted within 'es' is 'ERAS'.
'for the' acts as a link.
Can you help me to learn more?
(Other definitions for eras that I've seen before include "Long and distinct periods of history" , "Periods, ages" , "typeface" , "Epochs" , "Periods of time" .)