Hammers too heavy, tight pining on hammer flanges or rep lever, action spread incorrect causing geometry issues, rep spring tension is too low. Do the hammers fall dramatically when the jack is tripped by your finger? This would point to hammer weight/spring strength. I've found that some hammers are so heavy that they require a 'stronger lift' for the rep lever to support the shank and for the jack to reset easily. -- Regards, Jon Page
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