If I didn't reload AND I was buying a magnum bolt face gun AND I didn't want it to recoil I would want the chamber to look something like a 6.5 PRC or (possibly) a 7 WSM or 7mm RM.
In truth a 7 rem mag in a non featherweight rifle with a decent stock design is far from punishing, you can shoot a rem40x in 7 RM with 168gr or less weight SMK's for a 60 shot prone match as a sling shooter pretty easily, I wouldn't make the same claim for the same gun, for every shooter with a 300 WM shooting heavy 30 cals.
If a brake and/ or more weight is an option a lot of bigger magnums start to be viable "fun" shooting options.
That being said 2-300 yards @ 1 moa doesn't need 60+ gr of powder 223, 6mm (any flavor), 6.5 creed, 6.5x55, .260 would all be great paper punchers way past the range you were talking about along with a myriad of other options.
If you flip the paradigm a little and did reload AND had a magnum bolt face action, I might make the chamber look like a stubby WSSM and buy all the brass I could find and enjoy a really efficient cartridge w/ low recoil...