Model 37 Airweight

[12many]

Today I picked up a square butt Model 37 and I am trying to figure out about when it was manufactured.
I have the fourth edition of the Standard Catalog of S&W and i can't find this serial number.
It is 21J547. If I disregard the 21 does the J547 tell me it was manufactured between 1969-1970, and if that is the case what does the 21 mean.
I know someone here will know the answer.
Thanks, 12many (one two many)

 

[two-bit cowboy]

Smith & Wesson Historian Dr. Roy Jinks calls the serial number
series of your Chiefs Special Airweight the "roving J series."

He said the series began at 1J1 in 1970 and ended at 999J99 in
1973. Sandwiched amid two to five digits, one to three digits
before it and one to four after it, the J made its methodical march
toward the right. Serial number 9J9999 preceded 10J1; serial
number 99J999 preceded 100J1 and so forth.

Your Model 37 likely shipped in fall 1971.

 

[12many]

Thank You very much!!!!

 

[Hondo44]

12many, (one too many).