I was having issues with magazine indexing. I have ten mags, and all of them had an occasional "mag under rotation" problem.
Over the past few weeks, I've tried the things that Ed mentions in his video, but my problem persisted.
After studying the operation of the horizontal indexing rotary gear, AND the vertical piston (R2D2), I realized that the spring inside R2D2, on top of the vertical piston, was not strong enough to fully rotate the mag into position about 10% of the time.
So I put a 1/16 thick washer behind the spring inside R2D2 to give it more pressure on the vertical piston. I made sure that the spacer washer would not allow the spring to become coil- bound, when it compresses during its operation.
This completely eliminated my problem. I now have over 100 magazines through the gun since that change, (800+ shots), and not a single rotation problem.
I think my gun just needed a little stronger spring to allow that piston to do its job. I could install a little stronger spring, but
I'll just leave the spacer in mine for now.
I think the issue that my particular L2 was having, must be a tiny percentage of the guns out there, based on the little I've seen reported about it.
Anyway, Im really enjoying this mechanical marvel.
HTH
Scott