Has anybody tried 275gr, or 300gr bullets in a 340
Wby? I'm wondering if the twist will stabilize these
higher weights. Thanks

I haven't tried it yet but I did buy a box of the 300gr Woodleighs to try out in my .340 Wby. I've just got to find the time to load some and test them! From reading some of his posts here, I know that Ray Atkinson uses the 300gr Woodleighs out of his .338 Win Mag and he says he gets good results with them. I think he gets about 2400fps with them. Maybe he'll chime in on this post. I would think that if they stabilize in a .338 Win Mag then the odds are good that they will work in a .340 Wby. However, I can't remember the twist rate for the .340 Wby right now.

-Bob F.