how much does the mb effect symmetrical cores? I would think it would matter more the farther the pin is out on the ball. I'm wondering how much more that matters I guess or if it just doesn't matter and to only worry about pin placement.

Symmetrical cores generally do not have a significant mass bias - even if it is marked (e. g. on the Trauma cores). This is rather a help for the ball driller for the ball setup, but reaction-wise it is negligible.
Even some asymmterical cores only have a weak mass bias that will not need consideration in the ball setup to avoid critical layouts (e. g. some older Hammer balls with the "LMB" marking, or the Propeller core from Ebonite's TPC series).

As a rough rule, mass bias or PSA becomes relevant if the asymmetrical differential comes into the 0.012-15" area or more. But any symmetrical core, unless some mass bias is created through different core densities (that's why the RG diff. number will be an indicator if provided by the manufacturer), should not "suffer" from MB effects.
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DizzyFugu - Reporting from Germany

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