ARLINGTON, Texas – The United States Bowling Congress released a new research report on string pinsetters and the USBC Equipment Specifications Committee has approved final specifications based on the research. USBC will certify string pinsetters and string pin bowling as an independent category of equipment and competition effective August 1, 2023. The final specifications reduce the string length to a minimum of 54 inches.

Under those final specifications, key findings of this 2023 report include:

  • USBC’s lab data indicates strike percentage on string pin bowling will be 7.1% less than when using free-fall pinsetters.
  • This could result in average differences as large as 10 pins or more.
  • Unusual spare conversion rates have been nearly eliminated.
  • Additional testing is needed to determine if a conversion between string pinsetter competition and free-fall is reasonable.

This 2023 report follows up on previous USBC string pinsetter research that began in 2020. Results from an initial study were published in December of 2020 and another research report on the subject was made public in September of 2021.

In the 2021 report, USBC released the results of its initial phase of research on string pinsetters along with preliminary specifications that were developed to help promote similarity between the performance of the different pin setters and more closely align with free-fall performance.

Based on the results from the latest round of research, USBC has outlined the following next steps regarding string pinsetters:

  • USBC will certify string pinsetters and string pin bowling as an independent category of equipment and competition separate from free-fall machines effective August 1, 2023, for the 2023-2024 season.
  • USBC will conduct additional testing with an objective of determining whether string averages can be used the same as free fall or whether a conversion can be created.
  • USBC will provide an update on the additional testing and potential for conversion in advance of the 2024-2025 season.

The full 2023 report can be found on the

United States Bowling Congress
The United States Bowling Congress serves as the national governing body of bowling as recognized by the United States Olympic & Paralympic Committee (USOPC). USBC conducts championship events nationwide including the largest participation sporting events in the world – the USBC Open and Women’s Championships – and professional events such as the USBC Masters and USBC Queens.

Founded in 1895, today USBC and its 1,493 state and local associations proudly serve more than a million members. USBC is headquartered in Arlington, Texas, working toward a future for the sport. The online home for USBC is