Note that when two different charges of different powders push a given load of shot to the same speed the same amount of work has been done. The burning rates of the powders will determine which has its pressure peak the quickest & highest. If you calculate out the total pressure beneath the curves in each case they will be very nearly identical, they're just proportioned differently. This proportioning can of course be important. A powder that peaks too high can be Undesirable, obviously. Also a powder that peaks too low can be equally undesirable under many climatic conditions.
