Sorry KK, I just don't think you can so easily separate engravers from their contemporary art. Typically, decorative arts (carving, wallpapers, etc.) are influenced by other artistic styles, rather than the other way around. Look at jewelers and jewelry engraving - their work usually reflects other artistic influence (Paloma Picasso for instance). In this case, most gun engravers would have been mimicing the most obvious examples available to them.
In some instances, they were engraving a design supplied by the customer, who may have used a hunting print as a model.
You can actually find Art Deco shotgun engraving:
ART DECO - Art Deco was a popular international art design movement from 1925 until 1939, affecting the decorative arts. Art Deco is widely used in many areas as a decoration style, such as architecture, interiors, furnishing, fine arts, handmade crafts, posters, and industrial design. As hand engraved decoration, Art Deco is rarely found on firearms or custom made knives and is somewhat more popular among jewelry engravers.
Left is pictured the receiver of a Browning shotgun engraved in the Art Deco style by the late Felix Funken of Liege, Belgium.
You can see the photo at:
Art Deco Browning
I saw a Westley Richards sxs a year or so ago with Art Deco engraving - didn't look right to my tastes.
