An employee of Samuel Colt's, Rollin White,…
November 1856 CE
He had taken this idea to Colt, who had flatly rejected it and ended up firing White within a few years.
Colt historian R.L. Wilson has described this as the major blunder of Sam Colt's professional life.
Rollin White had leftColt's in December 1854 and registered a patent on April 3, 1855 in Hartford, Connecticut, as patent number 12,648: Improvement in Repeating Fire-arms.
On November 17, 1856, White signs an agreement with Smith & Wesson for the exclusive use of his patent.