I have tried 3 bullets so far, Nosler CC 77 gr, Hornady 80 gr and Barnes triplex 70 gr. The Noslers start coming apart at arround 3200, the Hornady almost the same 3200 to 3300. The Barnes are ok at 3700, but I would like to have more options for bullets. Do any of you have any experience with Sierra's? I am not looking for anything lighter than 70 gr. Twist is 1 in 8 on a 27 inch barrel. I did get the Hornady's and Nosler's to 3700, but only 4 or 5 out of 15 made it to the target. Loads are a bit warm, but with RE 25 I can probably get another 100 fps.