I noticed the most popular 7mm cartridges are the 7mm Rem Mag then the 7MM 08 Rem. Besides these two among factory load ammo shooters the rounds are still good like the 7mm Mauser, the 280 Rem, 7mm BR (some loads under loaded or comparably not popular) or the hot magnums SAUM, Rem UM, WSM, STW, WBY etc are not as easy to find or are expensive or specialty but still very good cartridges. For handloaders they have more options.