Does the barrel say "38 S&W ctg."?? (no Spl.)
If 38 special won't go all the way in, it might be a 38 S&W revolver. In a J frame
that's a mdl 32 or 33. In a 6 shot? Model 11 maybe? Possibly a Victory model M&P
in 38/200 that was cut down and plated?
DO NOT EVEN THINK ABOUT FIRING 9mm in it. Unless explosive disassembly sounds
like a good thing.