Different powder: better accuracy?
Please explain how this could happen:
Today I tried 2 loads through a service size 9mm pistol. Same 125 grain LRN, same primer, same OAL, but different powder. (Bullseye vs AA#5). Yet that gun liked bullseye better.
At the same trip I tried the loads in a second service size handgun and that gun liked AA#5 better.
Any clue what's going on here? I understand a barrel working better with different bullet profiles and weights (surface area) but not so much powder except for extreme cases like snub noses.