Originally Posted by
Thumpic
It may be hard to tell from the pic, but they are machine screws that are threaded through a spring and into/through the interior of the drop out. The slotted head of the screw would ride against the axle. I think they are installed backwards....
edit...I reread your post FB and your explanation makes sense. I think I'll turn them around though.......
You really don't want to do that. You want to leave it so they remove toward the slot rather than to the back. If the screw becomes damaged, it's easy to move it backward, clean up or saw off the damaged area then remove the screw. If you turn it around you'll have to do the surgery inside the slot, and if it should get sheared off the stud will be hard to remove.
The little end caps are probably still available, and will allow easy adjustment if that's your concern.