I don't have the book in front of me to date the gun, but if it is marked as a model 36 then that is a nickel plated finish. Smith & Wesson 38 Special revolvers with fixed sights are calibrated for 158gr ammunition. I believe on the S&W website somewhere it says that all the model number marked revolvers are safe for plus P, but it does accelerate wear on them so its best to shoot mainly standard pressure ammo at the range
That's a nice gun but the earliest it could have been produced is 1982 when the barrel pin was eliminated. And no later 1988 when the 36-2 began. So not a 1998 produced Model 36.
It's a pre dash gun,
It's a J frame, not a JM frame,
It has a forged and hammer and trigger, the .265" narrow trigger, and the old style cyl release thumb piece:
1986 - New standard trigger: .312” J frame smooth combat trigger became standard.
1995-96 - MIM parts introduction starting with modern style thumb piece with shaved off lower half, date varies by model.
1996 - August, JM (J Magnum) frame introduced.
1997-8 – MIM hammer, frame mounted firing pin, and hollow MIM trigger all introduced (date and dash number vary by model), and cyl stop stud (frame lug) made integral with frame.
May I ask where exactly on the gun that you found the # Ccs7259?