50 is enough, 60grs of loose better...Recently I sighted in friends muzzleloader and started with 80grs FFF Goex and a 240gr Hornady XTP, recoil was minimal...

You could let her shoot 50-60grs, the lighter 240 XTP and bump it to 70grs or so to hunt...She'll never know the difference in the field and I think all will agree that 70grs is "enough"...

Remember, the 45/70??? 405gr bullet and 70grs black powder, killed many, many buffalo...Deer ain't buffalo...

I've killed several with 50grs FFF and a .40 flintlock...