If the walnut stocks are truly original, would the serial number be located on the grips, as well? If so, would they be stamped, inked, penciled, or otherwise numbered?

It would be written in Pencil on the back of the Right Stock Panel.It can be very hard to see 100 Years later,Try holding the Right Panel in the Sun Light and viewing it from an angle.

It's surprising to me that Smith & Wesson would have regressed over 50 years, in resorting to simply penciling in the serial number on a grip. I am not doubting your answer, as it confirms what I suspected all along. A far superior method would be stamping the serial number on the grips, as they would have done in early 1862 on a Smith & Wesson No 2 of which I removed the grips a few weekends ago to examine. The 4 digit serial number looks like it was impressed on the inside of the rosewood grips only yesterday.

We are assuming it was one of those management efficiency changes that lasted several years and then changed back to stamped #'s again as a quality firearm would have. You know how those management directives are, not always for the best for a product.

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H Richard
SWCA1967 SWHF244

Throughout the 1920s decade, S&W penciled SNs. I thought in the teens, stamping was the norm.

You can also get a good feeling if they are original or not by how well they fit and the overall condition as opposed to the Gun.On My Triple Locks the Numbers have all been written in Pencil on the right Stock panel.I have One from 1908,One from 1914 and One from late 1914.