Modified S&W 1917, .455/.45LC

[Lee Enfield]

Hmm..interesting. What's the reasoning for that?
As far as I know, the ammo for these 1917s was jacketed from the very beginning. The 45 ACP certainly was.

http://smith-wessonforum.com/reloading/143635-455-vs-45-acp.html

It is a Second Model Hand Ejector .455, not an M.1917.

Part of the confusion is that while an M.1917 is a type of Second Model Hand Ejector, a Second Model is not an M.1917...

While Colt started heat treating their cylinders circa 1909, S&W did not until roughly 1918/1919.

Barrel steels were designed around cast (or even swaged) lead bullets, right into the .357 Magnum era.