Tap, rack, bang (TRB) or tap, rack, and go (TRG) is jargon for the response to a failure to fire in a firearm with a removable magazine.
[1] This is designated as an "Immediate Action" and involves no investigation of the cause (due to being under fire in a combat or defensive situation), but is effective for common failures, such as defective or improperly seated ammunition magazines.
[2][3] Some failures, such as a "stovepipe", require more complicated maintenance that requires investigation of the underlying problem, or remedial action.
[2] With issues such as a squib load or hang fire, the "tap, rack, bang" procedure should not be used.
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