There's some play when I lock my underfolding stock open. Not much, and probably what is the norm, but I'd like to know if there's a way to remove this excess movement.
Here's a link for how to dissasemble the underfolding stock. You have to knock out the pin that holds the retaining ring. From there you might (or might not) be able to tighten retaining ring one more notch. When you put the pin back in make sure you peen the pin on both sides or it will fall out.