Hevi Shot XII is not TSS. My state regs say with anything less than a 20 gauge it must be TSS shot at 18g/cc. This shot does not meet that standard. Not saying you cant use it where you are, just saying it is a pretty light load for a tough bird. I wouldnt use anything less than a .410 mag load of 9/9.5. I think the true .410 guys can give you the best group of ammo/chokes to sight in with. Good luck to your grandson. Z