I seriously doubt that the powder will get 100 grain bullets up to 3800 fps, that would beat a 257 Weatherby magnum that spits them out at 3600 fps. Maybe 3100 or stretching it to 3200 fps. Hornady is loading their 243 superformance with 58 grain, 80 grain, and 95 grain weight bullets. they are doing 3750 fps with the 58 grainer, 3425 fps, and 3185 fps with the 95 grainer. I am sure you can get fast with the 55-58 grain bullets up to around 4000 fps or slightly more. I think it will be a nice powder but we will see maybe 100 fps boost over what we have now.