SAW lists the following part:
SP61538 BOLT, STRIPPED (MPC or C)
I was taught that all Colt bolts are marked "MPC". Then I came across a "C" marked bolt when changing extractor springs. It didn't have the "MPC" but I knew it was bought from a reliable vendor as Colt.
Is there any difference between the two bolts other than the lack of "MP"?