Good advice. SAAMI specs. for 44 Magnum rifle barrels is .431" groove diameter, handgun barrels is ,429". Don't know why. My Puma in 44 Mag. slugs out to .431". I use a Ranch Dog design 240 gr or 26 gr. RNFP sized to .432"...
For my PCCs I have always started out with, and mostly stuck with...