I just purchased a new 15-22 a couple of weeks ago and it has significant buttstock slop. So, I replaced the original with a Magpul mil-spec CTR Stock.. better, but still has some rattle/slop.. anything else I can do to mitigate that?
I saw this method from youtube some time ago.
Take a two stripes (about 5 inches) of soft side of velcro and slap them inside the buttstock side by side.
This almost eliminated the slop.
I use Adaptive Tactical EX Performance milspec stock.
The key is to run the stripe all the way to the end.
I used the fuzzy side velcro strips. Worked great. Stock slides freely, and has a tight lock up in all the right places. I used aluminum tape on another. It had excellent results as well.