Feeling with a needle , the sprung bits of steel are curved, I think, so
original balls in there but fixed intentionally, or by rust, to the spring.
For ease of assembly , they were probably spot welded together. Like the
ferrite carying ends of springline/joy-spring reverb tanks the springs are
then soldered to the brass cylinders at their fixed ends
The problem was one of the anchors was slightly out of alignment , in one
attitude , by a couple of degrees and so the rotating pin of the barrel was
binding on the brass of an anchor.