Russian roulette

Russian roulette is a potentially lethal game in which participants place a cartridge in only some—typically one—of the several chambers of a revolver. The cylinder is spun and closed so that the location of the round or rounds are unknown. Participants would then aim the revolver at their own heads and pull the trigger, risking a likely death from the gunshot wound. It was famously portrayed in the 1978 film The Deer Hunter as a form of gambling, but the extent of real life gambling based on this activity is unknown.
The roulette in the name is in reference to the real gambling game of roulette since it also involves risk taking and the spinning of the revolver's cylinder is reminiscent of the spinning of the roulette wheel.
The form of the game can be as varied as the participants or their motives (displays of bravado, suicide etc.), but typically a single round is placed in a six-shot revolver resulting in a 1/6 (or 17%) chance of the revolver discharging the round. The revolver's cylinder can either be spun again to reset the game conditions, or the trigger can be pulled again, increasing the probability with every trigger pull: 1/5 (20%) for the second trigger pull, 1/4 (25%) for the third etc., going to 1/1 (100%) for the 6th shot. Using revolvers with fewer chambers (typically five) or increasing the number of rounds are other variations that increase the risk.


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A revolver, used in Russian roulette.