You are correct, my situation was completely different. I should have read the threads before responding.Glad it worked out for you, but it was quite a different situation and does not help the OP at all.
Please take a close look below at the B7100 manual page the OP posted in post #2 in this thread. Item 12 has been pushed out of alignment by spring loading and item 15 (special bolt) will not go in without disassembly!
The situation has been explained in this thread in posts #17, #40 and #43 in detail if you would read them.