Sometimes, it is just the wood changing. I have a gun here, that the stock came from back east. When I was putting it together, one evening I left the trigger guard sitting in the inlet, before I closed the shop for the night. Next morning, the trigger guard was on the floor, and the stock had began bending far enough I had to bend the trigger guard to catch up with the wood. That stock now has an off cast of over an inch. Fortunately, it fits me well.