HI Guys:

I have a CZ550 with a wood stock, I wanted to change out the front sling mount to attach a bipod. The new sling mount screw was slightly different in thread pattern, but I went for it anyway. On the last day of hunting season the screw stripped out. How do I restore the hole so the wood screw threads have grip? and never falls out again?

Just a suggestion but maybe drill out the hole to tidy it up, glue in some dowel and then redrill a new hole in the dowel for the sling stud. I haven't had to do this though so not sure how good an idea this is.

There should be a nut in the bbl channel that the stud screws into. Get it out and put a new one in.

If it was a wood screw type to begin with then countersink the inside for the above mentioned nut and install.

A little epoxy in the nut and it is fixed.

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That right there! I use bedding compound and it works even better

this and amuser's suggestions right on, the epoxy would be a problem if you wanted to remove for some reason (I take the front sling screw off when I am bench shooting) it seems to hang up where I want the pressure point to be

Put lots of release compound on the screw and the epoxy is not a problem and works well with a barrel channel nut, best of both worlds.

I don't know if your stock's sling swivel stud installation was intended to support the added stress of a bipod - if not you'll continue to have issues. If you have to do major surgery on the existing stud, remove the barreled action, and go into the stock from the barrel channel to minimize visual indications of the repair on the outside of the stock. Instead of the knurled nut that most studs screw into, I would get something large to bed in its place such as a 3/4" brass, knurled cylinder that's threaded 10-32 or 10-24, depending on which stud you have - of course you can always switch and get a new one (most common these days, is the 10-32 size)