Needham Conversion barrels started life as standard M1861/63 Springfield pattern barrels.
They were modified for the Needham breech-loading system by cutting off 6′ from the breech end, then reducing the diameter of the last approximate 1″ and threading it to accept the Needham receiver. All Needham barrels so far have been the same and the only differences looked for are stamps. Some have been shortened but it is not known if the the Fenians did this or if they were shortened in some later time in their life.
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