I just bought a colt sp1 carbine and I noticed on the bolt carrier that it has the serrations for a forward assist.But it does not have a forward assist.Is this the way they were shipped from colt new? Or did previous owner change the carrier out!!!                           Thanks in advance I do appreciate it!!!!

As Colt ran out of the smooth side (non-serrated) bolt carriers they did not see fit to continue producing them as the serrated carrier worked with the FA and non-FA uppers. There was no sense in producing both types.

The serrated carriers were then substituted on the SP1 assembly line. I don't think that there's an exact date or ser. no. available to denote this change. You can check for the stamped letter C on your carrier. This will at least tell you if it's a Colt carrier.

I bought my SP1 new in 1979...The bolt carrier is notched for FA. Serial # is below 100,000

Rick