How literal is this phrase?

Sample examples at http://tinyurl.com/is-it-lit

smoking gun:

Definitions:

  1. indisputable evidence (especially of a crime)

Examples:

  1. cause is often a breakdown in communication or record keeping and the hunt for the smoking gun ( the Post-It-Note on the job docket ) is the only way proof can be
  2. April A facility near Baghdad that a US officer had said might finally be " smoking gun " evidence of Iraqi chemical weapons production turned out to contain pesticide , not sarin
  3. Neo-cons move quickly on Iran PROGRESS OF THE PRETEXT * Britain finds Iraq 's ' smoking gun ' : a top-secret missile * Iraq Weapons Hunters Drop Outdated Leads NEW WORLD ORDER
  4. tapes , Vice Presidential Chief of Staff I. Lewis Libby was caught by a " smoking gun " that blatantly held pride of place on his desk in the White House --
  5. like this , you do n't expect much more information . There will be no smoking gun . All sightings confirm a multi layered coordination between Saddam and bin Laden , in

Note: Please select the answers below carefully based on the definition which occurs frequently in the examples

Step 2: score of 0-5 for how literal is the use of "gun" in the phrase "smoking gun"
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