https://en.m.wikipedia.org/wiki/Adolph_Alexander_Weinman The W is not a Mint Mark. It's the designer's initial.. W stands for Weinman
Noted already that this W is not a mint mark. I think there are at least two dimes that do have a "W" West Point mint mark. 2015-W "March Of Dimes" proof and 1996-W mint set strike. I would suspect that any 1996-W found in circulation is a liberated mint set coin.