I just got a Ruger M77 Mark II, synthetic stock and stainless steel. It's chambered in 30-06, and so far I've tried shooting premium ammo (Winchester Supreme 168 gr, and Federal Premium 165 gr.), as well as Remington core lokt in 165 grain bullets. But I'm not happy with the size of the groups. The tightest I can get are around 1 1/2" and sometimes larger, off the bench at 100yds. Now I know this gun can do a lot better than that. What other ammo can I try that might shoot better in this baby. I don't handload, but should I try it? By the way the barrell appears to be free-floating, cuz I ran a $1 bill through...:-)

Thanks for any imput...