Old gun stocks work fine, and in your case the price is right. For a release agent, you can use old paste wax, shoe polish(it is messy), or anything that is slick and has some substance to it. The trick is to have the glass bedding, epoxy, J B Weld, or whatever you use to be able to bond to the stock, and take the shape of your barrel and barrel block. Because this is your first, you may want to put a layer of some type of plastic wrap, the thin stuff like you wrap food with between the barrel, block, and forend for extra safety. The epoxy/ glass bedding stuff can make the whole thing into one solid unit if you don't get your relesae agent right. All it takes is just a little making contact in the wrong place. Been there and done that, as well as a lot of other guys out in the home gunsmithing world. That would probably be a good place to do a search. May find photos etc. You also want to fill any voids the epoxy/ glass bedding can get under or in on the barrel and block. This thing has to be able to be lifted back out after everything has set up. Look at it like your making an impression in clay or something, and you don't want it to tear, or be deformed as you lift the barrel out of the forend. Everything has to fit tight, but be removable. Hope this helps, do look for a home gunsmith site and ask around, photos are better than someone trying to explain without them. A DREMEL is worth the cost for this stuff with the right bits.
