I'm having trouble figuring out what model this revolver is and what year it was made. I've read that the "real" serial number should be under the grip, but my grandma (the owner) doesn't want the grip to be removed.
Well I can tell you it's a 3rd Model Safety Automatic chambered in .32S&W "short" and was designed for use with smokeless ammunition.
The 3rd Models were made from 1909 to 1941. I'll check the book tonight to narrow it down based on the barrel markings.
Even with the grip off there's a chance that the narrow range of years is the best that can be done.
There was a period of time when IJ did a separate serial number run without letter prefixes on "special order" revolvers. The 4" barrel, blued finish, and "Western" walnut grips were all special order options.
The barrel markings were used between 1914 and 1941.
If you convince grandma to let you remove the grip and there's no letter prefix the above dates will be the best we can do.
If there's a "G" prefix it dates to 1915 and a "J" prefix would be 1928.