You still need to verify with more accurate measurements, picture above is one type of .38 S&W (.361 bullet diameter)
If not that could be a 9x18 makarov (.364 bullet diameter) or the very common .38spcl and .357 mag both at(.357-.358)
Need something more accurate then the ruler, as far as date goes could be 1877-present I'm thinking 50's Just my opinion