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general::
Phrase(s): let someone have it (with both barrels)
Fig. to strike someone or attack someone verbally. (With both barrels intensifies the phrase; it alludes to firing a double-barreled shotgun.) • I really let Tom have it with both barrels. I told him he had better not do that again if he knows what’s good for him. • Bob was really angry and let John have it— with both barrels.
McGrawhill's American Idioms And Phrasal Verbs