Virtually every load has a different type of powder and a different charge.
Factory loads, and hand loads both carefully select the type of powder and charge weight to obtain the maximum velocity and energy at safe operating pressures.
I didn't fight to defend your freedom so you could vote to take away mine.
"A man who has nothing for which he is willing to fight, nothing which is more important than his own personal safety, is a miserable creature and has no chance of being free unless made and kept so by the exertions of better men than himself.
John Stuart Mill."