GENERALLY:   After the American Civil war, over a million and a half percussion muzzle-loaders were available and in service, but were also demonstrably obsolete.  Yet, financial constraints imposed by the great cost of the war required that if there was going to be a more modern arm introduced, it would have to take into consideration this vast number of arms "available" for use in some appropriate, but economical, fashion.  The outcome was clearly not the best possible modern breachloader, but the best compromise to be had, given money available and the desire to obtain more service out of the existing stockpile of arms.  This balancing resulted in the adoption of a breachloading mechanism to be fitted onto the Springfield muzzle loading rifle M1863.  Nominally "designed" by Springfield Armory Master Armorer E.S. Allin, the pattern resulted in pattent infringement suits by both W. Mont Storm and Col. Hirum Berdan, designer of the Spanish and Russian Berdan systems and a successful Civil War commander of note.   The first conversions made in 1865 utilized the original .58 cal barrel but  quickly proved  unsatisfactory, both due to calibre and an exceedingly complex extractor mechanism.  The next batch in 1866 were immediately successful.  These incorporated a simplified extractor mechanism and a sleeved barrel reducing the rifle's caliber to .50.  These proved servicable enough that the M1868 was produced utilizing completely new (shorter) barrels, with Allin actions built on M1863 percussion rifles.

PHOTO: The rifle shown is a US M1866 Springfield infantry Rifle converted from the M1863 Springfield muzzle loading rifle.

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DISTINGUISHING CHARECTERISTICS:  The M1866 is distinguished from the M1865 by it's simplified extractor and sleeved .50 caliber barrel.  It is distringushed from the M1868 by it's 40" barrel.  The M1868 is fitted with a new made, unsleeved 30 1/2" barrel.  The M1865 are usually marked "1865" on the lockplate tail, the M1866's were mostly converted from M1864 percussion muzzle loaders and are marked "1864."  The M1868's are marked "1863" or "1864" and are serial numbered on the left side of the receiver.

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MISC NOTES:   Note to potential collectors, that the same serial number as was on the receiver was also stamped on the barrel, as well as the receiver, just forward of the juncture between the barrel and the receiver.  So these two serial numbers are side by side, and if different from each other indicate that the barrel is a replacement, and not as originally manufactured at the National Armory.

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