while adjusting the feed on the magnum stoker, the wing nut would no longer stay tight against the adjuster & adjuster tube. the 5/16" threaded rod was no longer fully seated & tight into the pusher block.
to solve this problem (turn feed switch off) take the wing nut & bar adjuster off the threaded rod. install (2) 5/16 x 18 nuts back to back on the threaded rod & tighten against each other so neither moves. now just put a wrench on the outer nut & tighten the threaded rod back into the pusher block until tight. don't overdue it or you may snap the threaded rod.
perhaps others have had this problem & maybe this will help...even though the solution is pretty obvious.
regards to all,