So I bought a pound of RE 26 about 6 months ago with the plan of trying it in the WSM cartridges. All I have ever used is 7828 in my 7WSM with 145 and 150 gr bullets. I finally loaded some 162 ELDM's with the RE 26 and I am absolutely amazed with the performance. I am averaging 3,095 FPS from a 24" barrel and I am under book maximum. More importantly, this load is averaging under 0.4 MOA. This is from a Kimber Montana that I picked up in 2004 and it is topped with a VX3 2.5-8. Based on my results, I would think this powder would be great with 180-200 gr bullets in the 300 WSM.......if you can find some to try. I plan to try some ELD-X to see if they run as well and try them out during this year's CO elk season.