Here's the link to: ".455 British Svc Revolver Research Thread" a study of which barrels were Cartridge marked also showing many ship dates: thx to all the members that participated!
http://smith-wessonforum.com/s-w-han...ch-thread.html
While I was at it, I posted the latest version as of today.
David is correct, there is only a SMITH & WESSON MARKING; no Cartridge/Cal marking on the TL 455 BSRs with rare exception. Nor on many of the 1st 20,000 or so 455 2nd Models.
The TL 44s are most all marked, but the 1st of them thru the middle of 3 digit S/Ns were only marked "44 S&W CTG", but marked "44 S&W SPECIAL CTG" for the duration of production. Odd cartridge chamberings were almost never marked.