Unless you are a handloader, the .243 Win makes more sense. I have both, and while there is no doubt the 6.5x55 provides better penetration on larger game with the 140 (or even 160 gr bullet) at modest velocity, the lack of availability of both rifles and factory ammo suggests you pursue a different course. Use the .243 Winchester with good 95 or 100 gr bullets, i.e. Nosler Partition, and it should do the job on black bears with decent shot placement. The .260 Remington is also getting harder to get, although I have heard that Savage is planning on chambering their model 10 and 11's this year for it. But again, good luck finding ammo locally. You can order it online, but bullet selection isn't that great. I still plan to rebarrel my Stevens 200 .243 to .260 Rem once my son finishes shooting the barrel out. Probably the best option for a light recoiling rifle for off the shelf ammo and rifle availability would be one in .308 Win. or 7mm-08 Rem. Both of these recoil more than the 6.5x55 or .243 Win. If it was me, I would just opt for the .243 and use Remington Core-Lokt on deer and step up to Federal Fusions or Nosler Partitions for the bears. Of course, if you handload, then you can choose whatever caliber you wish and just find a rifle chambered for it, or have one rebarreled.