I had a friend who had a similar problem, the difference was that he had taken the action out of the factory stock and when he put it back in the rear screw caught just fine but the front screw was a bit short. I took a look at it and determined that when he had put it back together the recoil lug had not gone into the engaging slot in the action. With the action sitting on top of the recoil lug it was not really noticable as one would expect it to be.
Try removing the action and reinstalling making sure that the recoil lug is engaged before starting the screws.
drover
