For my 416 Rigby Improved, 10" twist, 34" barrel, for ELR target shooting the only bullet validated for 2000 metres is the 550g Flat Line solid copper G7 BC .637.
It is the only bullet I would consider, however, I have still not found a suitable HUNTING weight bullet in a VLD style, nor a HYBRID.
Cutting Edge has the 550g tipped hollow point which is also solid copper and requires a twist of 10" minimum, faster is better. G7 BC .525.
Bullets lighter than these are few and far between.
I would look up Cutting Edge, their bullets are for hunting and may fill your needs. I use them in my 375-416 Rigby Improved, when I can get them…
Cheers.