You didn't go wrong. Wood is always moving, and because of humidity and dis-similar wood grain and density this is what happens.
There was a thread not to long ago about this same topic. I did the same thing you did. Mine the stock was cut 1 1/2" and a recoil pad and extension was put on. I hate recoil pads and especially the look of that one. So I used a piece of walnut and I only fastened it on with two long screws, no glue no dowels and finished it. This way, at some other time if I want I could find a better suited piece of figured walnut to match more closely.
Last edited by JDW; 02/08/09 05:23 PM.
