I see mixed reviews on Hodgdon Superformance powder. I found a unicorn load of 46.9 grains for my 6.5 Creed. Shoots a 140 grain Sierra Tipped GameChanger 2901 FPS sub MOA accuracy with a SD of 6 and ES of 15 with no ejector marks or heavy bolt lift. This is compared to my H4350 load that gives me 2700 FPS with the 143 grain ELD-X.
That’s 200 FPS faster by using Superformance compared to my other pet load. I think I am lucky, especially for a hunting load.
Oh it definitely works and generally gets faster speeds than other powders for sure, my sole issue stems from how temp sensitive it is. I did the load work up in the winter when it was in the 40s but in the summer when it’s 80 my velocity spikes by 150 fps. I now use it to load 30-06 ammo that will be used only in the winter for the deer rifles and when it runs out I’ll be switching those loads to StaBall 6.5.
Your supply seems kind of flat to find a really good load for 264 or 260 or 243.just my opinion.I have several 8#ers of super, but yet haven't tried any. Going too see how it works for 264wm w/150smk at 1/7.5 twist. Also for 243win, 260rem, 6.5creed and 556. I wish QL would update powders and bullet info!