"Best" takes in a lot of territory but if we are talking shotguns & writing of a technical bent Michael Yardley is one of my favorites.
As previously mentioned, Sir Gerald Burrard's writing is excellent & informative but I always feel like I'm back in college reading a textbook when I read his stuff.
John Barsness is one of my favorite writers when it comes to rifles & handloading & Charlie Waterman for a non technical enjoyable read about dogs, upland hunting, big game hunting, shotguns, rifles & fishing.
