I am using H1000 for my 338LM as well as my 300 WM. For the 338, with 250 SMKs, H1000 works great. I haven't done much load development for the 300 SMKs yet, but plan to. I am trying to keep it simple here without having to buy 5 different powders. I might be open to trying H4831sc, but I have no prior experience with that one. Should I stick with H1000 or try another powder? In other words, are you guys able to get good results with one powder for both 250 SMKs and 300 SMKs or scenars?