Sound of mild explosion: a shot, I gathered, ending in salvo (7)
I believe the answer is:
atishoo
'sound of mild explosion' is the definition.
'atishoo' can be an answer for 'explosion' (I've seen this before). I'm not sure about the 'sound of mild' bit.
'a shot i gathered ending in salvo' is the wordplay.
'gathered' indicates an anagram.
'ending in' indicates one should take the final letters.
The last letter of 'salvo' is 'o'.
'shot'+'i'='shoti'
'shoti' is an anagram of 'tisho'.
'a'+'tisho'+'o'='ATISHOO'
Can you help me to learn more?
(Other definitions for atishoo that I've seen before include "Sound of a sneeze" , "Word to be sneezed at" , "Sudden eruption" , "Sneezing sound" , "hay-fever sufferer may interject this" .)