Perfect game (bowling)

A perfect game is the highest score possible in a game of bowling, achieved by rolling a strike during every frame. In bowling games that use 10 pins, such as ten-pin bowling, candlepin bowling, and duckpin bowling, the highest possible score is 300, achieved by bowling 12 strikes in a row in a single game: one strike in each of the first nine frames, and three more in the tenth frame. Because a strike counts as ten pins plus any pinfall in the next two balls, 30 points are possible in a given frame.

In five-pin bowling, the highest possible score is 450, as a strike is worth 15 pins. It is rare to bowl or witness one. The Canadian Five Pin Bowlers Association approves from 10 to 40 perfect games per year.

Before a 300 game is recognized by the certifying body of the league or tournament, a series of tests are conducted by the local or regional bowling association. First, the bowler and league (or tournament) must be in good standing with the organization. In earlier years, the bowling ball(s) used in the scoring was taken for testing (hardness, weighting, and other aspects that would otherwise break the organization's regulations). Also, the lanes used in the scoring were shut down after the last game of the day was completed. The official then used a tape reader to test the oil condition, to make sure it met the organization's regulations. The data was then sent to the certifying body, and the score received final certification or not a few days to a few weeks later.

There are cases where the tests do not meet regulation, and therefore the score is not recognized by the organization. However, the score still counts towards the league or tournament statistics. Modern recognition is much easier; lanes are no longer shut down, balls are no longer taken and inspected. The lanes are inspected once a year, and the ball's make and serial number (USBC only requires that the ball have an engraved serial number, they do not need the actual number) are taken by a league/tournament official and reported to the certifying organization.

In league or tournament play, a certified 300 game is usually commemorated with a ring. Subsequent league 300s are denoted by setting "chips" or precious stones into the ring, so that skilled bowlers don't have to wear several rings. The United States Bowling Congress (USBC) offers a "multiple" 300 ring for an additional fee that features the number of approved 300 games for that bowler surrounded by stones. The ring can be returned to have the number changed as the bowler rolls additional perfect games.

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Wikipedia