Mike,
Thanks for the posts. We can always learn something no matter how old we get. I had only collected the 1899 & 1902 Military variations with standard sights but what I like the most are Target Variations from 1899 to 1905, 4th. I never before paid much attention to the standard sighted models
Thanks for the continuing education credits.
S&W CFE by Mike Prewar at S&W University.
Perhaps these will help your research:
SN: 5501 US Navy M1899 NO caliber markings (barrel is original to gun)
SN: 19593 1899 M&P Target "38 S&W SPECIAL CTG"
SN: 62356 1902 M&P 1st Change Target
on two lines: "38 S&W SPECIAL" (above) "& U.S. SERVICE CTG'S" (below)