Bigboar, I have data on an LBT 400 M which was made for my Marlin by Veral Smith some years ago. This bullet weights 410 grains before gas check and lube. These are loads that I find best in my rifle and the H-322 load came from John Taffin in a article he wrote. IMR-3031 51.0 grains. Average velocity for 4 shots 1,785 fps. Very accurate load. H-322 52.0 grains. Average 4 shot velocity 1,844 fps. You will feel this H-322 loading on the back end! My Marlin has always shot it's best with cast bullets when they were 350 grains are better. The closer to 400 the better. Good luck.