Thanks for the info guys, keep it coming! With the 1:10 twist I decided to try a lighter/shorter bullet today. I loaded 100 gr Partitions over RL19 at 2600 fps. The first 3 shots were under 1" at 100 yards. Shots 4 and 5 moved a full inch to the right but the holes overlapped each other. I'm assuming its from the barrel warming up.

I only had 10 rounds loaded up to test so after running a few over the chrony I tried a couple at longer range. There is a steel plate up a steep hill at 313 yards so I set up my video camera to see where the shots would impact. I held high guessing that I would have a 16-19" drop. After I got home I watched the video and both shots were very close to my point of aim. I held too high and missed the plate though. Next time I'll hold on the top edge of the plate. Thats the farthest I have shot a handgun so far.