I shoot all of my loads out of a much shorter barrel but it gets the job done.When it comes to sub loads I do my own..Main reason, I take a 16 inch barrel and a 21 inch barrel and shoot my loads as I am trying different weight projectiles and powders.. It ain't a quick fix, it takes a lot of time and patience to develop a sub round, that will work for a specific length barrel with a certain twist rate. Since they all act different in different configurations...I roll my own...Good luck and thanks for the report..