I'm much of the way through restocking a fox...I had the blank fully let in and had checked function (I thought), and had the shape down to the point I was going to assemble it and check fit on a pattern board before final sanding/finishing. You know the rest of the story...I put it together to find that the right barrel functions fine, while the left barrel is not working...I believe it is not cocking, so hammer is lowering as the action is closed. All the parts appear to have plenty of space around them, and all the action screws are timed so they match the former stock. I thought maybe I had buggered something in working on it, so I reassembled on the old stock, and it works flawlessly. In comparing the two, the right barrel trigger pull (the only one I can compare) feels a bit lighter in the new stock.

Possible culprits? What's next?