By design there is should be a latch arm that hooks over raised ridge on the body of the alloy casting. It appears that this latch arm has broken off from the slider and this allows the slider to rotate out of position and jams the operation of the powder measure. This damaged can be prevented by insuring the dispense position indicator does not make contact with the top of the slot (see page 4 of instructions, step 5B).
To repair, please send the measure into Lee at the address below for service.
Lee Precision, Inc.
4275 Highway U
Hartford WI 53027
