I would like to see the long rumored Ballistic Tip Long Range (BTLR). Something like that might be less finicky than the ABLR to load. More options in the Solid Base line too.
257 130 gr BTLR
257 130 gr Accubond
257 135gr Solid Base
277 165 gr BTLR
277 170 gr Solid Base
277 170 gr Accubond
358...
I looked on their website and they are listed at 7.3 lbs and a 1 in 14 twist should be great for all but the really heavy mono bullets from Hammer and others. It will be fine for the vast majority of 35 cal bullets out there. The CVA Cascade seems to have a very good reputation too.
That's my favorite 270 cal bullet and it's on my list to work up a load in my 6.8 Western this year. Going to use Hodgdon's data for the 165 gr ABLR and work up slowly. Going to try Magpro first, what powders are you looking at?
This is their brand new design the HBC. Yes they offer heavier options in their other tipped bullets but these new ones are very sleek even compared to those.
As a fellow lefty I noticed that rifle too. Pretty tough to beat that package for hunting in grizzly country. I would get a supply of brass and reload for it myself. Weatherby makes awesome ammo but I'm sure you could get some great loads pretty easy.
Not sure if you're wanting info for the Ballistic Tip or the Partition. I've used the 100 gr Partition it's a tough little bullet. No experience with the 100 gr Ballistic Tip but there is good info in the above posts.