I am playing with the idea of having a custom barrel and caliber made for a barrel extention for my SRS. So here is the deal..I want it to be ballistically as identical as the 338 as possible to 1K. So that smacks of 6.5 for me. What do you guys recommend...with a 26" barrel 6.5 Lapua, 6.5 Creedmore, 260 Rem, 260 Rem AI, or 6.5-284? Well we could just go 264 Win Mag I suppose. I was thinking that for what I want to accomplish...the 139 Scenar from a 260 AI would about hit the mark.