Wow that is a question that could have pages of answers. Depends on how you will use it. Depends on how you are equipped. This is a long range site so here is one suggestion.
My friend has a 300 WSM
and asked me to help him make a LR load. The rifle is a browning A-bolt with 23" barrel and a boss. The 215 hybrids had not come out so I used some 230 hybrids which I had on hand. I really didn't expect much and was surprised at the results.
The magazine has a OAL limit of 2.8" which had that long bullet buried in the case. I chose RL-17 and worked up to a very accurate load for a velocity of 2720 fps! Didn't even need to adjust the boss system. His rifle has a Leupold with a M1 turret so he can range and twist for the longer shots.
If you want LR capabilities you could choose one of the heavier Berger match target hybrids like the 215. It should do quite well with RL-17.
If you are hunting normal distances the bullet selection is almost unlimited. Nosler, Hornady, Sierra, Barnes, Speer etc...choose your poison. There are many options from 125 gr to a 200 gr hunting bullets.