A look at a rare Colt Model 1855 sidehammer ‘Root’ revolving half-stock rifle (VIDEO)

A variation of Colt factory superintendent Elisha K. Root’s sidehammer revolver, the Model 1855 is often credited as being first repeating rifle adopted by the U.S. military.

Donated to the NRA’s National Firearms Museum as part of the Edward and Virginia Brandt collection, senior curator Phil Schreier shows off this rare bird which is in exceptional condition.

While Colt made some 17,000 Model 1855s of all types over a nine-year period in several barrel lengths and caliber options, the most popular were the half-stock model that Schreier has to show off. However, he has the less frequently encountered sporting variant, of which fewer than 3,000 were made.

So why didn’t these rapid-fire (for the time) rifles catch on? Potential chain fires on these cap and ball revolving rifles proved disastrous and, when compared to the Henry, Sharps and Spencer carbines which used metallic cartridges and came on the scenes around the same time, they just couldn’t compete.