I have been working up loads for my .338 win. mag for a month or two now. RL19 seems to be the best powder so far but i'm still not happy with my groups. I'm only getting 1 1/4" - 1 1/2" groups. I started with CT ballistic tip moly coated 200 grain and absolutely could not get any accuracy at all. I have been told that a 200 grain bullet may be too light for this caliber but I have also read where people shoot these fine. I have switched to 225 nosler accubond's and have seen a great improvement. Hopefully with some fine tuning i will be shooting 1" groups, that is my goal. I just purchased some Hornady sst 225gr but have not worked up any loads for this yet. Hope this helps and keep me posted on how you make out...........