All depends. Depends on the gun too, some of my mags hold more than others.
Walking solo, 2 mags, one for the pipe, and 2 of the plastic things that hold 10. So 31.
Posting, 6 mags, the pipe round and the 2 plastic things. Ran out one time, 51 shots got me 9 coyotes. So now at that post I grab an extra box. Any more than 50 isn't really realistic tho, too much barrel heat in the scope, but I like to be reloaded right away.
Gopher hunting depends too. Using the truck or golf cart and 10/22, I load up around 100 25round mags and just keep pulling them out of the bag, and throw the empties in a bin.
On foot I run 2 mags and dump a brick in my pocket and load on the go.