I shot a nice 4 point in velvet with the Federal Premium Berger Hybrid Hunters in .308. My tikka loves them. 100 Yard broadside shot to the heart/lung area. He stiffened up and tipped over where he stood. No exit wound, absolute carnage inside the chest cavity. Very little meat loss, So far...
Congrats on your purchase. I just picked one up in .308. I searched google and 35 inch/bs is the answer I found/use. Mine had to have the barrel channel opened up with a dowel and sand paper to free float. The recess for the bolt handle had to be opened up also to allow the bolt to close...