I have been really thinking about building a rifle with a shorter barrel. Right now all the rifles I have are 24” or longer and I do shoot suppressed so I think I would like something in the 16-20 inch range but having trouble going between a 6.5 creedmoor or a .308. Are these going to be pretty much the same out of a shorter barrel? I have looked at velocity charts and they seem comparable. What would you go with and why?