Hans Bauer gun maker ?

[Philip]

Eugen Heer, Der Neue Stöckel Vol I lists two smiths by that name from south Germany, although recorded as working in different cities:

Hans Bauer , Nürnberg, ca 1575
Hans Bauer, Esslingen (Württemberg), military records trace him to year 1604, and other documents show him providing arms on military contract 1616-17.

It doesn't rule out someone changing his locale of business in a long career, and there could be other Hans Bauers in the trade who have yet to be seen on other registers.

Good luck in your research!