Serial Number Location.

[P5 Guy]

S&W way back when put the serial number under the barrel, on the cylinder and on the extractor along with the butt and right grip panel. And I thought Luger was overboard.

 

[GunnyUSMC]

S&W way back when put the serial number under the barrel, on the cylinder and on the extractor along with the butt and right grip panel. And I thought Luger was overboard.

This was common practice on military firearms.