Fast twist 277 throated long, to accept, & stabilize the 165, or 175gr Matrix bullets if your reaching way out there. I love my 270WSM, but I live & hunt in Elk country, & my personal minimum for Elk is 270 on up.
I'm a big fan of the WSM. In fact I love that WSM cartriges so much that my first build is a 300WSM on a long action for launching 180, & 200gr bullets. But if I ever wanna push its limits on I can try a 230 Berger without cramping case capacity.
Call me odd but I'm just not much of a fan of "metric designated calibers". If you call it a .243 its ok, but if you call it a 6 mm I don't like it anymore. Same with .264 vs 6.5.... Weird mental block maybe? I dunno. I'm just weird like that Hahaha
Metric mental block & all, a .264/300WSM sounds cool for LR Deer, Antelope, & targets imo.
If Elk are on the menue, id personally go bigger. I'm fully aware that a number of Elk have fallen to .264's, & will continue to fall to them, but for me there are just too many better Elk cartriges to choose from.
Have you looked into the 375 Ruger parent case wildcats?
Good luck with your choice. I'm sure you'll be happy with whatever you choose.
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