install the mag plate and ensure it rotates freely on its own
then screw down (install) and increase tension on the screws (bolts) for the retaining ring 315590 and see what happens
I use a sish kabob pick inserted in the bolt holes of the plate to line up the plate and retaining ring bolt holes then I insert the bolts
if it begins to bind and stops rotating freely ..find out why
315950 needs the tappered side DOWN if my memory is ok and pictures of parts on the QD21
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