I don't know anyone who has done it off-hand (I'm sure some members here have done it), but I know the Magpul CTR stock incorporates a single-point swivel attachment into the body of the stock, and if I'm not mistaken, S&W redesigned the newer 15-22's with one in the lower receiver (I'm not sure if it's all of the newer ones or just the MOE models).
If you look closely (sorry I don't have a better pic of the stock on hand), you can see the mounting point towards the butt pad inside the A-frame:
Midwest Industries and several others make aluminum sling adapters that clamp on over the receiver extension tube. I drilled my receiver and installed a set of Uncle Mike's QD Sling Swivel Mounts, but some people might not be willing to take their lower receiver to the drill press (or their quad rail and AFG to the scroll saw and Dremel, for that matter.) Here's the thread for installing the swivels http://smith-wessonforum.com/smith-wesson-m-p-15-22/140262-adding-qd-sling-swivels-my-1st-gen.html
![]()
KZ from Botach. It requires some paracord if you want to run a Magpul MS3 sling.
... bad experiences with Botach, but for $20 I would be willing to give them another try (I never learn sometimes).