Marlin 336, .30-30, Lee .309-150-F when crimped in the correct groove is showing 1/8" long rifling marks on the bullet nose. ( .309-170 f is worse) Rifle has very short throat? Should I be reducing the charge by some specific percentage for this situation? Loads I'm using are light enough to not show any pressure signs, but may not be giving the result the original load was meant to. I am assuming that the load data was not developed in a rifle that was already engaging the bullet in the rifling. Gun shoots decent groups (not through playing with sizing, lubes, loads, etc.) so the engagement may not turn out to be an issue in the end. Closing the action, you can feel the pressure needed to get the cartridge all the way home.