My thoughts on this topic are that, for the most part, it's a waste of time. Unless you shoot hundreds of patterns, you haven't proven anything more than what that one or two patterns happened to look like, that particular day. There are more #5 pellets in a given charge of shot, than #4s, therefore the only way #5s would produce a "thinner" pattern would be if the pattern was also larger in diameter. This might also be true as larger shot usually produces tighter patterns because it deforms less than smaller shot. I'd suggest using the size recommended for the game you seek and see how it performs in the field. Time spent on learning to shoot better is far better spent than time trying to re-invent the wheel. Shot size selection for the game and choke recommendations have been well established, long before we were born. JMO, of course.
