NO need for a case gauge.I don't own a case gauge for 45 ACP yet, so I took the striker out of my Glock 21 and checked some at random while I was loading to make sure it would load and eject.
I was going based on what the Lee reloading manual 2nd edition had listed, it said 4.0gr minimum with 5.2gr maximum load, so I picked something in the middle.
Use the USPS flat rate method.
size the case.
plunk it in your barrel chamber.
"If it fits it ships" USPS