Well, it's actually easier if you follow a bit of the Factory's names.
From 1953-1973 the SA guns were called; Single-Six, Blackhawk or Super Blackhawk. In 1973,,, Ruger introduced the New Model Single-Six, the New Model Blackhawk, & the New Model Super Blackhawk. It says so on the frames.
The change occurred due to the internal action getting the safety transfer bar.
So from 1973 until just the last few years, we called the guns Old Models, or New Models. Everyone understood that.
All was fine and when the Vaquero was introduced, it had the same frame size as the Blackhawk. No problems.
Then came the New Vaqueros. Again, it says so on the frames,,,! But they had a smaller main frame, and the Anniversary Blackhawks also came with a smaller main frame.
Then the confusion began.
Some people want to call the Vaqueros "old models or new models." Yet, we already have collector nomenclature using "Old Models" to denote an action change. So, most of us felt the term "Original Vaquero" was best to use to describe the full sized frames, vs. the mid frames. (It's what I used in my post above.)
Also, at this point Ruger muddied the water by making it harder to determine which model was which, by reverting to the use of "Vaquero" for all the newest ones,, on the mid-frame.
So,,,,,,,,, when we discuss the Original Vaquero, full sized frame, we also say "when in doubt, look at the serial number. An Original Vaquero will have a 2 digit prefix, while all the New Vaqueros, mid frames, will have a 3 digit prefix.
In the Blackhawk lines, the mid framed guns are of the "Flattop" design.
Clear as mud now huh?
