Yes, I think the 5.56 will be around for quite a while but I think the 6.8 would be better, I trained on the Lithgow L1A1 7.62 and that is a great rifle/cartridge! but the 6.8 would make a good hunting rifle does anyone know of sporting rifles in 6.8? I think Remington is now making ammo but have not heard of rifles yet, the following would be good start

6.8 wish list

CZ 527
Browning BLR
Savage 99 (no longer made

)
Remington 7600
AIA Lee M10?