it's proven to be with the right bullet and proper shot placement. Never hunted anything that big or potentially dangerous but prolly bigger is better. All depends if you can stand "bigger" recoil and still shoot accurately.I elected to go with Federal factory 250 grain Partition loads for my Alaskan coastal bear hunt on Admiralty Island. They shot more than good enough for that purpose.
However, the first day of strolling around in that dense rainforest timber and seeing claw marks on the trees 12' up, I looked at that 338WM and wondered if it was enough gun.
Alaskan brown bears are magnificent, and scary, animals.
I have no absolutely doubt that the 338 will stop a big bear. In that particular situation I found myself in, "bear guarding" while my brothers worked a small stream for salmon, it was very dense timber and I wondered I could get a good (killing) shot off before the bear was on me. There wouldn't have been much time to react.it's proven to be with the right bullet and proper shot placement. Never hunted anything that big or potentially dangerous but prolly bigger is better. All depends if you can stand "bigger" recoil and still shoot accurately.