I am going to get a Criterion 20 vartarg barrel over the winter 24 inches long 1-11 twist for a small shank model 12FV in .204 ruger that will be the donor. From what I have been able to learn Re loader 7 and H4198 are the go to powders. Is this correct? I have also read that some people are using H322 and 8208 XBR and on occasion Benchmark. Has anyone used these or other powders? I have a good supply of h322, 8208 and benchmark and a little RL-10x and AA-2230 but no RL-7 or H4198. I have read that some Accurate powders are used to but I don't think I can lay hands on any more of their product. I only plan on shooting out to 200 yards and no hunting just paper punching. As far as bullets are concerned I am open to any of them, 32 grains to the 40 vmax. I am a believer in letting the gun tell me what it likes. Please let me know what has worked for you. Thanks.