Steve, Have you checked (and rechecked) the condition of the hammer butt buckskin and hammer butt felt squares? The buckskin could be severely (or mildly) indented, causing lots of drag (excess friction) until the bump is cleared. If the butt felt is compressed the jack tip could be sitting too far forward. Replacing these might be necessary, or perhaps bolstering beneath the buckskin. Patrick Draine
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