I have 2 300 WSMs and have only shot Win Supreme 150 gr ballistic silvertips. I would not say that they are the "best", but when I got my first 300 WSM, it was about the only thing readily available (and still is in my area). I haven't changed bullets because they shoot extremely well in both my guns. I have been looking at Federal Premium 300 WSM ammo and will be giving their 165 gr Nosler Partition a try during the off season. The 180 gr bullet weight controversy for whitetails has been beat around pretty good, and I still feel like it is not too much but more than is needed for whitetails. If I were going for elk though, I would want a 180 gr bullet. It is my opinion that the a 165 gr might be a good middle of the road.