Hey Charles, according to my SC of S&W 4th, your M&P pre-10 was probably manufactured sometime in '48 time frame. (I originally read the SN as C +6 digits. Thanks to Ken for the correct interpretation!)
I like this one a lot. I love those old round front sights.

Your 1917 Colt is gonna be a guess; I'm thinking sometime in the '20s, and because it has no martial markings, it's probably a Commercial model. I'm probably wrong about this one, but I'm certain someone with much more knowledge about these will help.

Hugh

I remembered that I had one previously:
This is what the butt would look like if military;


Bottom of barrel;



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