Brocock/BRK BRK Sniper XR Magnum .25 Cal

What is the velocity change with the transfer port adjuster? I was thinking of getting one of these in .22cal next year or the year after.
Here is a shot string, non magnum. 3 shots on each power level starting on the lowest. Being able to change power on the fly is awesome and you will use it more than you think.

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