I really don’t understand the need to push her to the 300WSM when she’s perfectly capable with the 243. Not to be offensive, but this sounds like it’s about you and what you want, not what’s best for her.
Some very good groups there given Accubonds can be very finicky. It would be my first bullet choice in the 300 WSM.
I've loaded for 7 different 300 WSM's going back to 2001. I always used H4350 and various 180's. in general, 64.0 grains gets 2,980 fps. I switched to 64.5 gr's RL17 and got 3,030...
My SPS login won't work at Nosler.com, and I'd be willing to bet all my purchase history was wiped.
Edit - yep, had to create a Nosler login. All my purchase history with SPS is gone.
46.0 Varget is the no-brainer of the century load. This has worked with any number of different 165's I've used in my 308's. TAC is also a great 308 powder.
IMO, one of the best buys in the scope world. When anyone new to Montana asks me what they should equip themselves with as a new hunter, I tell them to get a Tikka T3 in 270 Win, and put a Burris FFII w/ Ballistic Plex on top in Talley Lightweight rings. One and done for life.
I realized I only indirectly answered your question - as lefty315 said, of those you have, I'd use whichever of the 165 BT or AB shoots best. I've used different caliber Ballistic Tips on elk, and they've worked great, and I'd be content to use the 165 NBT for the rest of my life for all my hunting.
The 308 is famously easy on bullets, and any of those you list will work well. The 308 is my favorite round, and here in Montana I've taken quite a few elk with it. I've never used anything heavier than a 165 gr. Energy doesn't kill animals, a bullet in the right spot does. I've cleanly taken...
Because a 308 is far more shootable to most people than a 300 or 338 WM... energy doesn't kill, shot placement does.
I've taken elk with everything from the 7-08 to the 338 WM. Hit right, they all died - a cartridge's shape and capacity is the least of the killing equation...
Shootability, shot placement and bullet construction trump headstamps. The other day a friend here was talking to a local outfitter that runs bison hunts on a famous local ranch. They have taken around 25 head a year for many years. He said the cartridge that stands out for the quickest kills...