Well if the 6.5 PRC is not doing it for you go 6.5 RPM it’s a hot rod 6.5 cartridge, I had GEF build me one on a Kimber Montana 84L and it’s crazy accurate, shooting the 156 Berger’s at 3070 FPS into a tiny little hole.
The 6.5 PRC is an amazing cartridge, very accurate with factory ammo, you’ll see by this next summer there will be many brands of factory ammo besides Hornady, Federal, Nosler, Barnes, not to mention all kinds of brass options, Hornady, ADG, Bertram, Gunwerks and now Lapua, the 6.5-300 WSM won’t get that kind of support,
but in the end if you handload it really doesn’t matter build what you want that way it won’t leave you wishing you did.