5/16 Rule

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Developed to allow the user to properly measure the ring finger of a fingertip grip when using the BT Ball Fitter.

The BT Ball Fitter WAS NOT developed to measure the ring finger directly on the device, it’s intended use to was to only measure the middle finger.

  1. First step is to properly measure the middle finger. For more information about how to measure the middle finger, click here.
  2. Draw a line on the crease of the ring finger.
    Mark ring finger crease
  3. Bend the hand slightly to mimic the radius of a bowling ball.
    bend fingers slightly
  4. Draw a line on the ring finger which transposes from the middle finger.
    Transpose middle finger to ring
  5. Measure that difference between the lines drawn in steps 2 and 4. This is your 5/16’s Difference.
  6. Plug in that measurement into the following formula: 5/16 – DIFF.
    • ex: 5/16 – 3/16 = +1/8 (Ring finger will be 1/8 longer than middle finger)
    • ex: 5/16 – 3/8 = -1/16 (Ringer finger will be 1/16 shorter than the middle finger)

Spectre Settings for 5/16’th rule auto-suggestion

  1. Goto the Settings
  2. Turn ON “Ring Finger 5/16 Rule Difference”
    5/16 settings
  3. When inputting a spec sheet. Input a middle finger span, then select the ring finger. Inside that popup, you will now be presented with either the measurement or the difference. One will move the other. Enjoy 😉
    Dropdown 5/16 rule
  4. The value in the 5/16 rule drop down is the equivalent to the measurement you took on the bowlers hand. This option removes the need to do the mental math to calculate the +/-
    Ring calculation 5/16
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