Tac just might be the go to powder for these two cartridges. Handloader Magazine just had an article and loaded both to there bolt action potencial. The 338fed being new is there already but 200 grainers at 2700 fps and 225's at 2500 fps for the 358win thats moving. Its a good read shows its a good 300yard round and may be more. "Not just your dad's brush gun"