Either the 150gr. or 165gr. Mono's would work perfectly - GMX or Barnes TSX or TTSX. I found the 165gr. Copper Trophy Federal ammo shot very well in my .300 Win. Mag. I do not know if they are available for handloading.

I would not use a cup and core lead bullet for deer or pigs in .300 mag.

I would, however use a 180gr. cup and core bullet for those animals and perhaps a 200gr. Nosler Partition for all.

Friend of mine uses that bullet in his .300 WTBY Mag. for whitetail and mulies in farm land. Blows their little melons off and causes no meat damage.