RE: .30-06 springfield question
The best thing to do is buy a few boxes of different types and grains of ammo and see what the gun likes best. The bullet grain refers to the weight of the bullet. I have a Rem. 742 that shoots 180 PSP Rem. corelokts good, but won't group very well with the same bullet in 165 or 150 grains.Go figure!
I suggest buying a box of rem. corelokts, winchester super X power points,and federal nosler partitions in either 150, 165, or 180 grains. And, use whatever groups best with your gun.