AR Upper and Barrel Identification HELP needed

[JaxNBosley]

I purchased a 1974 Colt SP1 lower that had this upper w/ tear drop forward assist, 24" heavy barrel (pre ban based on bayonet lug), and DTA Mil Brake on it. Neither the upper, nor the Barrel have any identifying markings (beyond "5.56" on the top of the barrel in front of the front sight) and I have not been able to find anything via google etc to identify either. Any help dating, identifying, etc. would be greatly appreciated.

[cvgunman]

Does the upper fit the lower? Good chance if it does it is a Colt as well

[JaxNBosley]

Yes, it does fit on the Colt SP1 lower, however the upper does have the smaller front pivot pin hole (.250) as opposed to the Colt .315, so there is a "cam" pin that is used to hold it in alignment. There are no "c" "m" etc (or markings period) markings anywhere on the upper or barrel.

[FLIGHT762]

You have an M-16A1 mixmaster upper and unknown mfg. barrel. It is not a SP1 upper since it does not have the .315" pivot pin and 1974 SP-1 uppers at that time did dot have forward assists. 1974 uppers also had triangular hand guards and a 20"barrel.

The only thing you have that is Colt is the lower.

[JaxNBosley]

So is the mix master upper worth anything? Or the barrel? I was able to find the original colt smooth side upper, complete BCG, Triangle hand guards and bird cage suppressor, and also Colt 3x20 scope too....just had to do alot of digging to get there.

[bohoki]

maybe its olympic arms that handguard looks sort of familiar but i cant place it