Yes I know that the .243 isn't an elk cartrige, but with a hold together bullet and a hunter that knows the limitations of their equipment then it will work fine. I would also rather have my son use a smaller, lighter recoiling gun / cartrige that he can shoot well than have him use one that he is shy of shooting and flinches with because it kicks too hard. If he couldn't get the bullet to the target then the bigger cartrige isn't going to do him or the elk any good.