I had an issue similar to the OP's on my 650 and it had nothing to do with the sizing die.
I had just refilled the primer tube and for whatever reason a primer got twisted sideways in the primer magazine. I could not pull on the handle without major resistance.
I thought the reason was the sizing die as well until I disassembled the primer assembly and found a mashed primer.
I had just refilled the primer tube and for whatever reason a primer got twisted sideways in the primer magazine. I could not pull on the handle without major resistance.
I thought the reason was the sizing die as well until I disassembled the primer assembly and found a mashed primer.


















































