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Colt SP1 Bolts Early vs. Later


Smooth sided bolt carrier without notches. Bolt itself is chromed. This unit came from serial number 159.

Image Courtesy Don Francis


Notched bolt carrier for use with forward assist. These assemblies utilized a cotterpin instead of the earlier split pin, to retain the firing ping, and also stopped the use of chrome in finishing bolts.

Image Courtesy Don Francis



(Top) Early model chromed bolt carrier. (Bottom) Early model split pin for retaining the firing pin. Images Courtesy Don Francis
(Above left) Early carrier that is machined to semi-auto specs. Contrary to popular opinion, early model SP1s did not ship with M16 bolt carriers, as this unit, serial number 159 shows. (Above right) Later carrier with more material machined away from the rear of the carrier and in the firing pin area. Images Courtesy Don Francis.  



Last Modified on October 4, 1999