Have you thought about a 7mm 08? It is mild recoil, I know a number of youth/women who use this chambering with no problems. It does offer some advantages over others in the low recoil class in way of the .284 bullet used and best part no need for a brake or BOSS to be used. I also suggest buying and installing her a good recoil pad, this will make a difference vs the factory ones most rifles come with when it comes to felt recoil.