I do recall a gent who posed that very question to Walt Berger, his reply was (i'm paraphrasing):
The reason they are not labeled as recommended for hunting is because Berger had not conducted sufficient testing to ensure their effectiveness. He also went on to state that he would have no issue with using then himself in a hunting situation.
I sure hope they work! I have a box of 6.5mm 140 Hybrids awaiting my 6.5WSM
I would expect them to work.... but i've been wrong before..... once....