Well, lots of shotgun powders have dual application(red dot, green dot, unique, WST, WSF, many more)
The faster burning powders such as red dot, WST, etc are ideal for low intensity loads, cast bullet loads, in most any popular pistol caliber.
The Hodgdon online data shows multiple loads for 9mm and .40 with longshot so you can compare velocity/pressure, etc. Note that longshot is considerably slower burning than 231 so you will need to use more for similar velocity using same bullet, etc.
No data is shown for tightwad but looking at shotgun data it seems to be much faster burning, close to red dot and much closer to 231 than longshot. It is a relatively new powder which may explain the lack of data or perhaps Hodgdon wants to keep it with the shotgunners. They burn a lot more powder. This link covers it pretty well.
http://thefiringline.com/forums/showthread.php?p=3562578
I have never compared standard and magnum primers side by side but with a supposedly longer and hotter fire you would assume there likely will be some pressure increase.
Look at the data, start low and work up
