The only bullet I reload in 7mm Weatherby is a 160gr Nosler Partition. Not for any particular reason except that it is what my dad had in 7mm bullets in his reloading supplies. I actualy get great results with it though. Sub MOA. Always better results than factory ammo.
I am getting ready to switch to new bullets as my partition supply is
starting to run low. I plan on trying both Berger 168 and 180 VLDs, Barnes TSX, TTSX and MRX in 140gr to 175 gr, and Hornady 178 AMax. The only brand carried locally is the AMax and I bought a box today. I will be loading and shooting over the next few weeks.
I look forward to trying the Barnes bullets though. I use them exclusively in my AR10 (.308) for hunting and absolutely love them. I have not found their accuracy to be better than anyother brand bullets, but I feel their terminal performance is awesome.
I've got a Hart 10" twist on my 7STW. It shoots the 162gr A-Max very well and provides good terminal performance on thin skin game.
According to Berger, conditions "would have to be right" for their 180gr VLD to stabilize in a 10" twist. That's to iffy for me. You never know what conditions you may be hunting (hot, cold, high altitude, low alt., etc) They added that their 168gr VLD would "definately" work in a 10" twist.
Depending on when it was built, the prevailing twist could have been 9.5 -1. In a 7 Wby you should achieve very good accuracy with the 160 class bullets. The good ones have been mentioned - 160-168 grains. I doubt the 180 would be a good choice but you can try it. The 160 Accubonds will tolerate very close range shots without blowing up. The last deer I killed in the Paw Paw Bends was with a 28 inch Shilen 9.5 twist 7 Wby and 160 Accubonds at a range of 50 yards. Not a lot of meat damage for such close range. Has a decent BC but because of the tough jacket and long bearing surface it is may not get you as much muzzle velocity as some of the softer bullets. But the softer bullets leave me unhappy with the amount of excessive damage they produce.