I am new to reloading starting just over a year ago. Reloading mostly pistols because I bowhunt. But I used to own a 300 WBY. I shot factory ammo. I was a stupid teenager at the time, but with my father's help I managed to harvest 5 elk with the rifle. I shot 180 gr. nosler partitions. When I did my part, it killed them dead on the spot. I also harvested a number of mule deer with the same rifle. It was not overkill. Provided you hit behind the shoulder and not on the shoulder, you will not waste meat. I'm sorry that I'm not familiar enough with loads for the 300 WBY to give a good recipe, but I do know that if you stick with a 180 gr. bullet you can't go wrong.