I would recommend that he try shooting the Rem 721, with reduced recoil loads, such as these;
https://www.remington.com/ammunition/centerfire-rifle/managed-recoil
https://www.hornady.com/ammunition/rifle/30-06-springfield-125-gr-sst-custom-lite#!/
https://hsmammunition.com/low-recoil/
https://www.remington.com/ammunition/centerfire-rifle/managed-recoil
https://www.hornady.com/ammunition/rifle/30-06-springfield-125-gr-sst-custom-lite#!/
https://hsmammunition.com/low-recoil/