More than one barrel used in shooting (5)

I believe the answer is:

butts

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'more than one barrel' is the definition.
(butt is a kind of barrel)

I don't understand the remainder of the clue.

(Other definitions for butts that I've seen before include "Target area" , "Target range" , "Victims" , "Ends" , "Objects of ridicule" .)

I've seen this clue in The Guardian and The Globe and Mail.

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