350 Legend
Well I may be a bit behind the times here but I see that Winchester has come out with a new cartridge called the 350 legend. It looks like it would be a great cartridge for those area that can only use a straight walled cartridge. Other than that I really don't see any reason for someone to go trade in their good old 35 Rem. Yeah with the newer designed bullets and in a bolt action rifle it may perform better past the 150 yard mark. But IMO a Leverevolution bullet out of your 336 can be so close no deer or blackie is going to know the difference.
Not this may in the near future be another option for the AR platform.