I once replaced the feet on my bipod, and after that it lost the auto-retract. I used it for a while, till one of the legs bound and wouldn't move.
So I took it apart.
It's a tough piece of equipment. Built like a tank, no plastic bits anywhere. Took a day to figure out how it comes apart - ingenious design .
Every screw has thread locker, I had to use a gas torch on all of them.
Turns out the retaining pin through the foot passes through the eye of a spring that is internally connected to a second pin at the the top of the leg. When I removed the foot originally, the internal spring dislodged. A bit of a file inside the lips of the bushing guide for the legs got them moving smoothly again.
I put it back together without incident, the only casualty was the cover on the tilt lever, it was aluminium. I replaced it with a steel washer.