thanks for all the input... I am, like Von Gruff, loading for accuracy and it seemed to me that the 64-65 charge was promising and feel tempted to play with the seating depth. I have also read and heard from experienced reloaders that many times the best node is close to max, and was wondering if I should keep pushing and if 0.5gr might just go over the node.

I have a 505 scale, but the 0.1gr and Standard deviation example is well taken. Maybe I'll try 65.3 and 65.6 for pressure signs... if accuracy is not there then I'll toy with the seating depth.