What caliber is the 1886? Is it original?
The 1861 isn’t a very common replica. It’s a Navy Colt from 1851 that they made to look like the 1860 .44 but as a .36 caliber.
The 1886 is a 40.86; one of the original 5 calibers. I have a confirmation from Winchester that the gun shipped from the factory around 1895 (I’d have to find the confirmation to get the exact date).
The Colt is the US 1861 Army Model, 44 caliber. It was the model issued to the Union forces during the Civil War. The 1851 Colt, .36 caliber, was the Navy Model.