I shoot the PD 180 grain FMJ, but not with TightGroup. I gave away what TightGroup I had, three years ago. Nuff said there!
I use CCI 400 small rifle primers, and 5.4 grains of WSF powder. Out of my (Limited) 4.5" XDm the power factor is 172.
For my (Production) 4.5" XDm, a CCI 500 primer and 5.6 grains of WSF is required to make a power factor of 170.
May I ask why you gave it away, were you unhappy with the performance, too dirty...etc