M16 - 121003-1
This is only the 3rd Colt Model 621 that I have seen in 30+ years. I sold one off this web site many years ago (see 240901-6). The serial number of this unit is within a few digits of the serial number of the other. This weapon left the Colt Firearms Division with a standard M60 machine gun bipod mounted on a very heavy barrel, just behind the flash hider as pictured in the jpegs below. A locking ring just behind the flash cage keeps the M60 bipod in position. This extra heavy barrel is marked “C MP Chrome Bore” as you can see in the jpeg to the right. The bipod legs are spring loaded like the standard M60 bipod and fold back against hand guards when not in use. Later a similar model M16A2, model 741 left the factory in the same configuration, sporting the same M60 bipod set up.
Several things to note. One is that it came in with an A2 pistol grip on it. I have no clue as to why, but either the original was damaged and replaced or the prior owner wanted to update it. It is my intention to correct that. Also, as you can see in one of the jpegs, the flash hider has a tint of green. I received it that way and will attempt to remove that, when time permits. I will not replace the flash hider as it is the original.