Whenever I got my first(And only chance!)between buying a ..38 Diamondback made in the first year of production(1966)-or, a .22 Diamondback made in 1978, the early model Diamondback had more of a blue tint to it(And, in direct lighting it appeared to also be slightly lighter in color!)than the later model Diamondback! The later Diamondback had a blacker looking blue color(Although still beautiful, I liked the first year bluing better!)however, I missed out on buying both of the Colt Diamondbacks-because the dealer was supposed to hold the (1966).38 Diamondback for me(Until I had returned the next day to buy it!)but, instead he sold it to someone else(The SOB!)! Although I wanted this first year(Low serial numbered!).38 Diamondback, at least I was glad that I had purchased the 1978 .22 Diamondback(On the spot!)or, I would have lost it too! This taught me a hard lesson! Now, I'll never leave a gun behind(That I desire!)left "Unpaid"(And, I won't trust any Gun Shops to keep their word, anymore!)!
bhh, I think you may be asking a question that may be very difficult to answer unless you had 100 various DBs spread out spanning the 66 to 86 time frame. I can tell you I have a half dozen DBs in front of me from 1966 to about 1980 and though there is some variation in degree of polish and depth of blue I can't seem to pinpoint one year or series of years as one better than the other. They are all nice. Like cars or any thing else, it would depend on the particular finisher, polisher, temperature of the bluing bath and when it was changed last or whether the gun was made on Monday. As we have said before, the degree of high gloss polish, especially on barrels varies, but I don't think you can pinpoint to any particular year or era as better or worse, if you can, good luck.
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