I perhaps learn ammo's run out withdrawing south (5,7)
I believe the answer is:
roman numeral
'i' is the definition.
(I is the Roman numeral for one)
'learn ammo's run out withdrawing south' is the wordplay.
I cannot quite understand how this works, but
'run' could be 'ra' (I've seen this in other clues) and 'ra' is present in the answer.
This explanation may well be incorrect...
'perhaps' acts as a link.
Can you help me to learn more?
(Other definitions for roman numeral that I've seen before include "Such as V, X or L" , "I for one!" , "I, perhaps" , "Eg, X or V or M" , "I say" .)