As ButterBean mentioned, HH's also require slightly faster powders /more of it to achieve full potential.
Look at load data and choose a powder with lower fill % to give you room to add more powder. HH's also exhibit lower engraving pressure, so you can use more powder to get to pressure/velocity. Not as pronounced as Absolute Hammers, but still present.
Look at load data and choose a powder with lower fill % to give you room to add more powder. HH's also exhibit lower engraving pressure, so you can use more powder to get to pressure/velocity. Not as pronounced as Absolute Hammers, but still present.