my brother inlaw inherited a model 10 (m&p) revolver from his father-trying to find when it was made for him,has 165xxx on the bottom of the grip, and n with a #5 and 87xxx inside the frame where the cylinder closes any info appreciated
Based on the serial number you gave, it's a .38 M&P Model of 1905, 3rd change. It was made between 1909 and 1915. S&W didn't assign and stamp model numbers until 1957.
my brother inlaw inherited a model 10 (m&p) revolver from his father-trying to find when it was made for him,has 165xxx on the bottom of the grip, and n with a #5 and 87xxx inside the frame where the cylinder closes any info appreciated
Is the 165xxx preceded by anything? Like a S or C?
No web site, but the book Standard Catalog of Smith & Wesson 3rd Edition by Supica and Nahas is the reference that many use for details about serial numbers.