As 308tikka said, try several brands and weights. You will find several which are outstanding for any quality rifle.
I always start with some cheap military surplus, to get on paper. Then I shoot some match ammo, my handloads or Federal Gold Medal 168 gr, to get a baseline of its potential accuracy.
Then I begin with the inexpensive hunting ammo, by PMC, Prvi Partizan, S&B, Federal Classic, Winchester, Remington, and Hornady - just a few of them. Now I know what common ammo I can buy in a pinch on a hunt away from home. I shoot a 5 shot group at 100 yards, and another group at 200 yards, to check accuracy and actual muzzle velocity and drops.
From there, I go to proven handloads which I have found to work well in all my rifles, with bullets I know to work on intended game.