Thank you Alpo.No sir. The 1866 Winchester was made up into the 1890s. Long after the 1873, and the 44/40, came on the scene.
The 1860 Henry and the 1866 Winchester were made of a metal called gunmetal. This is a bronze alloy, and is much stronger than brass. You will find many places where they talk about the brass framed Henrys and the brass framed Winchester yellow boy, but they are wrong. Brass is an alloy of copper and zinc. Bronze is an alloy of copper and tin, and is much stronger. This would explain why all these brass frame copies of cap and ball revolvers shoot loose quickly, while 1860 Henrys and 1866 Winchesters lasted for 50 60 70 years.
Anyway. These bronze frame guns were strong enough for the 44 Henry cartridge, which was loaded with between 25 and 30 grains of black powder. The 44 Winchester centerfire was loaded with 40 grains of black powder. Winchester came up with it when they came up with the 1873 rifle, which with its iron frame was much stronger than the bronze frames of the previous guns, and could take the more powerful cartridge.
There is a very nice discussion about the Henry centerfire, with both when and why it was invented, on this site.
That was a well thought out and informative reply.
Much appreciated. -b