I made it out to the range again and applied some of the inputs received here.

Namely:

1. I used a Lyman long crimp die to hold the 545gr boolit in place
2. I ran a 410 bore mop down the tube after each shot
3. I uniformed each piece of brass....length was pretty close on all, but a light touch with the RCBS case trimmer got everything exactly the same

I shot 11 with 110 gr, which did the best and had my brother's shoot some with the 105, which did not fare as well.

This was my target with 11 rounds of the 110 gr load.....didn't keep the other targets

[Linked Image]

First shot was the one on the left in the black. The remaining 10 shots are in the white.

This is an improvement over the previous two sessions so I am encouraged.

Thanks again for your collective advice. I'm looking forward to the next round of experimentation.