For Black Bears they are all great. For Grizzly, .358 Winchester- too slow not enough energy. .338 Federal, I honestly can't say about this cartridge, it's too new and unproven, but I don't feel the energy would be there. It's parent cartridge the .308Win is totally unacceptiable. .350 Rem Mag-The bullet is too light. The 350 can only be loaded with a 200 grain bullet and still fit into the magazine, a 225 or 250 grain bullet is too long. I know this I own two of them. Of the three the .35 Whelen is the only one I fell is suitiable for Grizzlies or Alaskian Brown Bear. The Whelen can be loaded with a 250grain bullet. For the Brown Bear it is the suggested minimum.