I have shot an Elk with the Nosler Partitions and they are unsuitable for ELK with the large bones the bullet seemed to break apart and not provide the kind of devastation that you are looking for.

I now hunt exclusively for ELK and Bear with Federal Ammunitions Barnes Triple Shock 180 grain out of a 300 win mag. These bullets are solid as they come and really will knock an Elk down in its tracks.

Kevin