What makes a complete rifle battery?

I have been exchanging emails with my nephew on what makes up a complete rifle battery. Lets define what we are attempting to assemble. That is "The rifle chamberings needed to hunt all the species of big game and varmints in North America".

Varmints will be prairie dogs, coyotes and anything legally hunted weighing less than 50 lbs. One might consider this is a big challenge. Actually it is not. If one wants to do it with as few rifles as possible, it can easily be done with as few as three rifles.

Let's break the task into categories. 1. Varmints, prairie dogs, "gophers" and coyotes. 2. medi...