Road agent's spin

The road agent's spin, also known as the "Curly Bill spin" (after Curly Bill Brocius) was a gunfighting maneuver first identified in the days of the Old West. It was utilized as a ruse when forced to surrender a side arm to an unfriendly party.

Normal Old West procedure for surrender of a loaded pistol called for it to be handed over upside down and butt-first. A well-trained gunfighter could hold the pistol upside-down by the trigger guard using the index finger and extend it toward the surrenderee as a false sign of compliance. When the surrenderee reached for the pistol with their (presumably dominant) hand, a sharp, practiced motion of the wrist would quickly flip the gun forward and back into firing position, catching the surrenderee off guard and unable to react.

References

* [http://www.time.com/time/magazine/article/0,9171,892441-11,00.html The Six-Gun Galahad] at Time
* [http://www.straightdope.com/columns/040625.html Did Western gunfighters really face off one-on-one?]
*Marks, Paula Mitchell: And Die in the West