My 14 Y.O. grandson wants to let him Deer hunt with my Browning 1885 Rifle with a standard barrel. I have tried light loads with 405 gr. bullets and he is developing a flinch. I have heard many people shoot a cast 300 gr. bullet for Deer and they work well. I always felt a .45 cal. bullets that light was on the border line of being a Pistol bullet and might not work. Do they ?.