1860 Army vs. the Dragoon: 1 lbs. 6 oz. lighter, smaller frame, creeping loading lever (rack and pinion), new “Silver Steel”. 

Silver Steel was probably a marketing term for a higher carbon steel that gave about 30% increase in strength.  Nick highlighted a number of errors on Colt’s part. 

Probably the costliest was alienating the Chief of the Ordinance Department and Congress.  Congress went so far as passing a law prohibiting purchase of “patented” arms.

In June 1860. Colt came up with a Model M to meet those requirements.   But by May and June of 1860 the superiority of Colt’s revolvers was confirmed in trials, and some Model 1860’s were produced in late 1860.  At least 2,159 were shipped to southern states before April 16, 1861.  Most – including those shown – may have stayed in the South during the Civil War..

View the complete presentation here.