Hey,
i worked on such a gun long ago, but havent the modeling skills to make it fancy^^
so i want to share my idea with you ;-)

your actual "gatling gun" looks more like a "gatling cannon" ;-)
(so i would like to work with you on a nice mod with that model :)

i suggest to use the gatling turret barrel, make it a bit bigger to fit and about 1.5x-2x longer to look awesome (i used the original size - was a bit tiny^^)

another thing is that i noticed a visual/mechanical downgrade of the gatlings (small ship & turret) - arara (responsible for some tracer mods) had an old turret in one of his mods wich uses every barrel... hard to explain - atm gatling turrets fire awkward from the center of the barrel (where actualy is no barrel to shot bullets from ;-) but the old model fires them correctly from the actual 6 barrels ;-) (sadly i didnt have such old model from the 3-barrel gatling guns :-( )
so i can upload you this old model if you want :)

due to steam/valves stupid decision to make steam guard mandatory for community comments (like yt did with google+) i cant comment and we need to communicate via keen swh forum or private chat if you like my idea :)

sorry for the "fast english" - hope its not to horrible :-/

greetz
brd