I would bet that probably 99%+ of deer are shot at less than 300yds.

300/400yds is a long ways out, but most stand cartridges can certainly take a deer down at 400yds or more. so ya no need for a .300RUM to shoot a deer at 300yds.

I kinda laugh at the "flat shooting cartridge" saying, all bullets drop! some are flatter than others, but it's really not that much more usually, ie dead on at 200yds, at 500yds, whether its a .270wsm, or a .30-06, both are droping lots of inches! it's not like 6" vs. 50"

so ya I think a good ole .270win can drop a deer at 500yds,