My suggestion is glue it and clamp it, the rubber bands, surgical tubbing works good, but you have to get the glue joint tight. Before you glue it examine the broken pieces at the break are for splinters, if there any unless they are on the edges of the stocks exterior, remove them, they will not permit you to getting the tight joint that you want. After the glue has dried, like overnite,it's best to drill a hole from the toe and into the remainder of the butt and glue a dowel in the hole.If the gun has a toe plate, I'm guessing it doesn't, the toe plate will hide the dowel. Point of fact is, that's what the toe plate was designed to avoid, toe breakage. You can use a 1/8" dowel. When drilling the hole try to get 90 degrees to the break. You do have a small break though. The dowel repair may not be neccessary. To hold the pieces from sliding use painters tape to minimize this. ...Geo.