This is a bit outdated--from 2015..
I see a lot of comments on 9mm or 22LR--don't think either of those qualify as most common LONG RANGE cartridge..
https://www.chuckhawks.com/best_selling_rifle_cartridges.htm
ARTICLE EXCERPT BELOW:
The .223, .308, .30-06, .30-30, .270, .243, 7mm Rem. Mag...