Here's a question for some of you folks. Building this rifle for my brother-in-law as a 'bonus' for doing a bunch of work on the house last summer. I've got a Stiller Pred single shot action (short), and a 31" Rock 5r 6mm 1-8tw barrel. I also have about 500+ fireformed brass and suitable dies for the 6mm-284 and since I already supply his 'reloading stuff' figured I'd use that brass. So onto the question. Is that 1-8 twist going to tear up bullets if I choose the 6mm-284? I am curious how fast you can shoot the 105 A-max and if the 284 is just 'too much'. Other option is the 243AI, but I don't have the dies or the huge supply of brass. Which would you choose? Barrel life shouldn't be a big concern as he's just a plinker, and wants a rifle to shoot to the far side of the field on coyotes behind his house (and to show off a little I'm sure). Lets hear your opinions.