Four years ago I did the “10 years of the Colt 6940” post and then a few days after realized I had left out some pretty neat stuff from the history of the Colt monolithic uppers. Over the last 10 years there was some other monolithic upper rifles and carbines from colt in some variants that we never saw displayed at any of the shows

This rifle length barrel and monolithic rail was very interesting. It came about right around the time the USMC was making noise about putting collapsible carbine type stocks on the M16A4. Supposedly making it the “A5” Never happened and neither did this variant. I would very much like to have had this gun but with a match barrel on it for a sort of 694X SPR precision rifle.

This is sort of a compromise of a M4 with a RAS but with the 6940 type folding front site and a piston gas system. Meh.

Above is a piston version of he Colt SCW. We did later see this side folding and collapsing stock trickle out via ebay and gunbroker etc. But so far nothing has been offered for sell as a standard or special order option. Later photos of more refined versions showed a DI gas system and a full monolithic 6940 upper. The side fold stock is pretty nifty but required a much modified bolt carrier group.

The most successful of the 694x series variants for military markets is the Colt IAR. Made up as Colt’s option for the USMC IAR rifle the Colt IAR is made up with a heat sink in the lower removable handguard and barrel more suited to full auto fire. A decent amount of uppers were sold on the civilian market,Howard has one, and some other countries use the full auto military version as IARs and even a sniper support weapon in the case of Mexico.