Does anyone know the years that Colt made the original 14.5in CAR-15 series carbines? Mostly I need to know what year they started production, and therefore how early they could have appeared in Vietnam.

The FAQ on Old AR-15.com has everything about these guns BUT the years they were manufactured!

Well there is a Colt ad in the book The Black Rifle, page 287, which shows the Colt family weapons. The text says it is from c. 1970 and there is a M653 looking carbine there. But as far as i know, no 14.5" barrelled weapons were used in Vietnam.

Prototype 1970/71
Production 1973/74

They were made until 1985 when they were superceded by the Colt Model 723. It's not likely that any made it to Vietnam as we were pulling out by 1972 and at the time the 653 was in just being developed.  Model 653s were purchased in small quantities by the US Navy, Army and Airforce until 1984/85

I dont know if there are many Model 653 in action pictures on the net, but here´s one:

Tuuka:

Is it your best guess that those are what Delta was using in BHD?

I'd love to have a 14.5" LW bbl.  That must be one heck of a quick handling little rifle.

Delta Used Colt Model 723( 14.5"A1),733(11.5" A1/A2) and 727's( 14.5" A2) in Somalia. They may have had rebarreled 653's but I doubt it.

The 75th Rangers issued the Colt 653 to M67 90mm recoiless rifle gunners. There's one in the back of the photo. It was also issued to platoon leaders, RTO's etc....like the XM177 series was to anyone that needed a more compact rifle in Vietnam.

The 653 was also purchased by the Department of the Navy for SEAL and USMC Recon units.  The USAF bought several thousand for SpecOps/SAR/PJ and SP personnel as well, these lack the FWD assist (Model 654).