1680 is good in the pistol cartridges and it also works well in a .22 Hornet or 17 Hornet. If you use real heavy bullets in the .357 you can load it down to subsonic with 1680. With primers, I would pick one that will do all of what you load for, once you work up a load with a primer type just keep using it, some times a hotter primer can reduce pressure in a load, so just start low and work up. CCI makes a bunch of primers for all sorts of loads, I just use CCI 450's or BR4's in every thing that uses small rifle primers or small pistol primers, they are hard and will take whatever pressure you have in the case, they are great in the high pressure cases like a 17 Remington or 17 FB and will work in the .357 cases. Larry