I loaded up some 10mm loads last Saturday using 8.5gr of PP / 180gr XTP bullets, and was off 4 or 5 inches off at 7 yards. The only thing I can think of is that my crimp was off, or I need to adjust my charge. My factory G20 (other than sights) is normally right on with 180gr Underwood XTP loads...Thoughts

Hi,

Are you saying it is not an accuracy problem but rather a "where the bullet hits the paper" problem?  The Underwood load, while a great load, is a red hot fire breather compared to your reload.  It is probably doing more than 200 fps more than your reload.  That is more than enough to move the bullet placement on paper. 

Power Pistol is a great choice behind the 180 XTP.  I can't imagine the crimp would make any sort of practical difference for bullet placement.  I think it is just a pure horsepower kind of difference.  Unless I missed something (not unusual)

Kenk, if your bullets are off by 5" to 7" at 7 yards then it is either you or the sights moved.  Are they grouping or scattered?

Yeah...that is 60 minutes of angle change..or 1 degree.  So, what was the group size?  This informs if this is just a point of impact shift, or both a change in precision and point of impact.

Hey folks, I hope to load up some more this weekend and see what I end up with. I do have some watered down factory target Stuff I will also try.
Thank for the input

Ken