Don,
I think that what your seeing is powder horns that have a waxed or oiled surface.
There are a few makers who like to use electric buffers, but I like the hand buffed satin look of a horn. To me, shiney powder horns look to much like plastic.
On all of my horns, and after shaping and filing. I sand the surface down with gradual grits on sand paper to 320 or finer grit and do a vigorous hand polishing with #0000 steel wool before adding three or more coats of a high quality paste wax.
Rick