Bleh, i just edit my own guns on my Fubuki.. It's not that hard really to edit ammo amount and reload/recoil..
For Sub Deck guns see either USSubParts in Library folder, or GerSubparts in Library.
Then just adjust the gun you use on you'r boat to you'r liking.. I'd suggest making backup first though, because eventually you'll get bored of it ^^
My guns on fubu (6 barrels of 5"ers) fire at ever .5 second ^^ autoloaders