[A1A]

Actually, it's 1964, going from 6,000 units to 10,600. This site goes a few years past Proofhouse.

As an aside, the same authority includes a disturbing statement: "According to Colt, it was designed to shoot 2" groups at 15 yards." Can anyone confirm or deny this? By contrast, Manurhin designed and built the MR-73 to shoot 6-shot groups into 25mm at 25 meters.

This site also goes to 1985 if you look in the DOB sticky post. Proofhouse is based on data published in TBOCF. "Extensions" are based on data published in Colt, An American Legend. That's it, at least until the new TBOCF.

I think it is an error to presume that all the numbers assigned for a year were used. All that is published is the starting serial number for each year. Notice that the starting number for each year is a nice round figure. Now, you might argue that they should end in more zeroes if they were really assigning blocks, but who's to say. Other accounts, perhaps in TBOCF or elsewhere that I don't recall, allude to Colt assigning blocks of numbers and reserving blocks of numbers. So, the production numbers generated by simply subtracting presumed serial numbers is clearly inaccurate, but it is difficult to say by how much in any given instance. Another problem is the difference between production date and shipping date. According to some accounts, the dates in Colt records are shipping dates. However, serial numbers should be stamped when a gun is produced. Guns could have been produced within a year's serial number range, but not shipped in that year. I agree that it is still interesting that, if preassigned well in advance, there would be a bump in the 1964 assignment, but the point should still be well taken that neither the number of guns manufactured nor shipped in 1964 nor any other year is known for sure. Perhaps the actual flow was smoother than simply subtracting the assignments implies. Perhaps the number assigner was bad at math.

I thought that Manurhin thing was argued into the ground in a previous thread. Remember that the Gun Collectors Club is just a personal website that, in addition to descriptions and opinions about the owners guns, simply reproduces other published material subject to the original publishers research accuracy. I believe the owner was or is a member here but I don't recall for sure.