I know some BLRs and even BARs have been built in .416 Taylor as well, again with the longer (relatively speaking) action in .300 WIN Mag as the starting point.
I am sure you would need to add a very good recoil pad, and maybe some extra weight and porting too as the BLR is a relatively light gun. Then again, the quick handling characteristics are part of the appeal.
It would be cool to have a takedown with a two barrel set in .300 + .416!