The book lists 4.0 gr. as top load, but I think it could be higher. Different books list different combination's max and min. I wouldn't go lighter than about 3.2, as with a semi auto it may not reliably function the action. With a revolver, possibly 3.0. I work up a load starting at minimum, and stop when I get the best accuracy. The load I chronograph'd at 906, was through a 2" barreled 940, and functions my 469 fine. Changing anything, such as the OAL, primer, or crimp can affect the velocity, pressure, and accuracy. Load small batch's of say 10 rounds, and test each .2 gr. change of load.