Has she considered maybe a 7mm-08 with managed recoil rounds. With a lighter bulltet say 140 grain even though it may be slower than 100 grain .243, the 7mm-08 will do better fighting crosswinds and has more oomph down range. There is only a slight difference of powder capacity between the two calibers of 2 or 3 grains. The recoil may be a slight increase but recoil is highly subjective.