I have worked with this several times over the years, by looking at shot sabots and realizing that some time all the rifling marks are on the petals of the sabot and some times they were not I came to the conclusion that to make an improvement on accuracy I had to-get them indexed so that each petal had two rifling marks on it. You have to work this out for each gun but I believe it makes a difference in how many of the close fliers you get.