S&W generation numbers

[The_Antibubba]

I have a S&W Model 66. I've noticed that the newest ones are the 66-6, with a key lock, and I've seen earlier ones with a number after the dash, but mine does not. Can anyone tell me the reasons for this?

 

[Standing Wolf]

In theory, the number following the hyphen indicates the significant engineering change. They're not actually anything that could legitimately be called "generations." Some changes are more noteworthy than others.

 

[Majic]

Yours was the first of the M66 series and was made somewhere around 1970 thru 1977. In 1977 they came out with some changes made to the revolver and became the M66-1. This continued all thru the history of the series. As engineering changes were made the dash numbers changed to show this.

 

[Jim K]

If I understand correctly, the "dash number" indicates a change that affects parts interchangeability. So when parts are ordered for, say, a 66-4, S&W knows if that part was affected by the change and can ship the right part. They are not really "generation" numbers, since not all changes were made on all guns at the same time, nor does a given number mean the same change on all guns.

Jim