When I opened a small hole in my goose egg I use my cordless drill and a small screw 1"wood screw. made the perfect size hole. I just went in far enough to make the hole then started chipping away shell. I knew she was gone though before i started. Can you tell any difference in the way your eggs feel from each other like weight and warmth. Asking because on the day before the gosling dies in the shell the egg was warm the next day when I picked up the egg and my goose was still sitting on it I could tell right off there was something different it was not as warm as day before.