Hello. I assume that Weatherby factory ammo uses premium bullets. Anybody know for sure?

I was at the range yesterday with a friend whom I'll be taking elk hunting this fall. He was shooting both a .270 Winchester and a .300 Weatherby Mark V Vanguard.

I examined the bullets in the Weatherby factory ammo (original ammo not reloads) and they appeared to be Nosler Partitions. They looked identical to the NPs in my .300 RUM.

I explained to my pard about pemium bullets, etc after noticing that his .270 factory loads were standard core lokts. I told him that if he decided to use the .270 on the hunt, he would be much better off using a premium bullet and that he should sight in with whatever he was going to hunt with. I recommended he go with the Weatherby.

Hence back to my question topside about whether or not Weatherby loads its cases with premium bullets. I would think so but wanted to get the straigth word.
Thanks in advance.