Quote:
Remember, even though the bullet would be lighter from the hp, it is still the same length as the heavy bullet so seating debth, thus powder charge, will stay the same.
Technically, surface area vs. weight deviation means the lighter boolit of equal surface contact offers less resistance, thus decreasing pressures of equal charge--meaning charge increase by weight ratio of weight decrease is necessary for equal pressures within the burn rate of the powder chosen... ;) But we're all following the common practice of load it normal and ladder it up accordingly. :D