So I think of figured out what's going on with the Magpul butt stock on my MOE 15-22. It looks like the spring loaded pin is not putting any pressure when the pin is in one of the "location holes". When the stock is not in on of the detent positions the stock is nice and wiggle free.
Here's a very short vid I made of the wiggle. Note, the wiggle is the same in every 'detent' position of the stock. I'm a little chagrined (to say the least) about the quality of this stock.
IMG 1397 - YouTube
That looks to be irregular. I'm not sure who you contact about warranty issues, Magpul or Smith&Wesson (I'd start with S&W). While the MOE stock is known to have a little wiggle (and I do mean little), what you are experiencing there is not normal. You should get a replacement.
Having that said, putting some of the soft side of velcro along the tube under the stock helps take out any remaining wiggle if you are (like me) too cheap to shell out the money for a stock with friction lock (or something else that eliminates wiggle) for your .22lr
I bought the MOE version to get the Magpul stuff but as I have advanced things started falling off. Now I don't have a single Magpul item on her anymore.
Speaking of Magpul...
Primary Arms has sale on CTR stocks for $57. That's as low as I have ever seen them.
Only thing I want that the MOE version has, is the sling mount...