[Charles Martel]

Yes, transitioning from black powder to smokeless is something that should be approached with caution. However, the Winchester 1886 action was originally loaded up to .45-90, IIRC, putting it near "buffalo gun" status early on.
The .50-110 smokeless chambering is pretty common today, though I'd base such a rifle on a new/reproduction action. The '86 design is stout beyond belief.

[yarddog]

Yes the 86 action is plenty strong.

Winchester changed their steel around 1895 to handle smokeless powder. I think the 30-30 was the first smokeless powder cartridge.