Originally posted by Prince Harbinger The focusing ring seems to be jammed on the 50mm. I can't move it.
Probably somebody dropped it. The inner threads on the aluminum focusing ring get jammed slightly cross-threaded and immovable. You can see someone tried hard to turn the focus until the grip came unglued. You can strip down the front of the lens (typical Pentax build) until you remove the external focus ring, and see the aluminum ring it was attached to has a slight tilt. Pry up the low point and it'll eventually snap back into place. The lens should work fine after that except no grip. Maybe a candidate for experiments, pretty hard to sell.
Someone really wanted to disassemble that M50/1.7, carved themselves two new spanner slots.