My long awaited 338 Lapua is almost finished. Just wondering what powder those of you with 338 Lapuas pushing 300 SMK's are using and what kind of velocity you are getting with a 26" tube.
I use H-1000. I would start about 88 gr and work up to 90 durring barrel break in while watching for pressure signs. My SMK load was very happy at .062" off the lands with a CCI 250 primer. Once you get the barrel broke in and ready for groups work up in 1/2 gr increments looking for the sweet spot. I would think you will get 2750 somewhere around 91 gr. Unless you have a Broughton 5C barrel then you may see a bit more. I would not worry about th last few FPS and would consentrate on group size at 200 or 300 yards.
Thanks for posting all the info fellas! I'm working up loads for my 338 LM with H-1000 too and it seems to be a very stable/consistent powder. I'm going to do some work with N-570 too, so we'll see how that goes . . .