[MagKnightX]

I guess the title says it all, really.

[RON in PA]

Suptle things like the shape of the hammer and lockplate. Also the barrel bands on the 1863 don't have retaining springs. The 1863 was only made at Springfield Armory while the 1861 was made there as well as many private contractors. From the viewpoint of shooting there is no difference.

[Jim K]

There was also the so-called Special Model 1861 or "contract model" 1861, which had a different hammer shape and some other differences from the regular Model 1861 as made by Springfield and other contractors. The "contract model" (sometimes called the "Colt Model 1861" since it was originally made by Colt), was also made by Amoskeag, LG&Y and EG Lamson, successor to LG&Y.

The most prominent feature of the regular Model 1861 is the "humpback" shape of the hammer, which is a carryover from the Model 1855 where it was made to fit around the Maynard primer. Springfield apparently kept the hammer shape because there was no reason to change it and because of parts interchangeability between the Model 1855 and Model 1861. Both the Special Model 1861 and the Model 1863 used the "S" shaped hammer.

As Ron says, there is no difference in shooting among the three (four if the Model 1855 is counted) models and there was no distinction made in service issue.

Jim

[4v50 Gary]

The National Firearms Museum in Fairfax has an 1855 Springfield lock that along with Maynard tape primer on display. Some Lawrence priming pellets for the Sharps rifles are also on display alongside of it.