I have been reading an old book "Handloading Ammunition" dated 1926 by J. R. Mattern and he mentions in several chapters about the optimal pressure ranges for smokeless powders. Generally he talks about shotgun powders having optimal burning qualities around the 10,000 pound pressure level with a usable range from 6,000 pounds up to 12,000 pounds. And of course pistol powders having optimal pressures of 20,000 pounds with a range of usefulness from 15,000 to 25,000 pounds. And similar for rifle powders. Has anybody seen recently an actual listing of this type of information for available current production powders? We can only get hints of this type of pressure/optimization range of powders by comparing the weights of powder needed to get to a certain velocity in the reloading manuals, by looking down the listings under a particular bullet load/velocity/pressure.