I think you would have to cut the buffer tube and then fill it with JB weld or some kind of epoxy. Then somehow clamp it on or drill a couple holes in it to run a nut/bolt through into the receiver.
It would be a rough mod... More so on the stock side than the polymer 15-22. It can be done... If done right.
Just remember, that's a lot of torque on that connection when your transitioning from folded to unfolded and vice versa.
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