Show lack of tact producing a ring? (4,1,7)
I believe the answer is:
drop a clanger
'show lack of tact producing a' is the definition.
I don't know anything about this answer so I can't judge whether this works.
'ring?' is the wordplay.
I cannot quite see how this works, but
'ring?' could be 'clang' (I have seen 'Ring of metal' mean 'clang' so perhaps 'ring' could also mean 'clang') and 'clang' is located in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for drop a clanger that I've seen before include "Blunder seriously" , "Say something very embarrassing" , "Say something tactless - make stupid blunder" , "Be indiscreet" , "Make a conspicuous mistake" .)