824tsv: As we've all come to find, & know, S&W's relationship between the SN# & Spec Order# (ship date) is a twisted one. I just looked at my 4006's box label & your's was made 36 days
after mine but it has a SN# 6400
before mine.
Poohgyrr: I bought mine lightly used about a year ago & don't have anything to provide you on your topic other than they're awesome guns, like all the 3rd Gens. It is suprising that considering it was the first for that cartridge (40S&W) & one of the earliest, if not the earliest 3rd Gen release, that it wouldn't have more notoriety?
.
4006 box label
(-01b)
.
4006 & 4056TSW
(-01a)
.