[Scorch]

I use AcraGlas for stock repairs. It makes a nearly invisible repair if done right.

Mask off the outside of the stock so you don't booger it up by dripping glue on the wood, then work the glue into the crack or use a syringe to force it in, then clamp tightly (make sure the pieces are lined up right!!). If you are concerned about it cracking again, you can drill a hole from the back of the stock across the crack and insert a screw or a hardwood dowel and glue it in place. Once the glue has cured, redrill the buttplate screw hole so you don't crack it again when reinstalling the buttplate.