In BC, where 99% of Stones live, you can only take one Stone every 3 years, unless it is inspected and determined to be older than 8 years old. So if a guy went out every 3 years and was lucky enough to get a ram each time it would take at least 12 years to shoot 4 rams. Then add 4 of each other species. You're talking 16 animals. 20 if you are including Californias in the slam. Even with a lot of coin, a guy has to be getting up there in years to accomplish 4 NT grandslams. Just my thoughts. I could be wrong though. Have been many times before.