The Nosler 260 Partition and the Sierra 250 GK will both perform admirably at the velocities you are working with.

What powders are you playing with?

If I were building a lightweight 'mountain' rifle in 375 calibre, this is certainly the cartridge I would use.

Hmmm... I think I need one of those

Keep us posted and welcome to the forums. Your post on the 'current SS' thread was informative and appreciated.