Thanks, guys. I've been googling for a few days and I have more sensible answers here than I've managed to find elsewhere. I'm mostly interested in a safe starting load. I can take it from there. Based on everything I've found, I will start with 22.0 gr. of the good 2015, examine the first case shot very carefully, and twist the knob till I've found group happiness.
Everything is different with the falling block action... finding a jam is really different than with a bolt gun, etc, etc... I asked for this when I decided to make an old style bench gun, 50's and 60's style. Thank God, it's easy for me... my bench is 20 ft. from where I'm sitting. If I get it shooting well enough to give the guys in Factory Class a hard time I will be very happy. This is my fortieth year of BR competition and my expectations are different now. Best summarized, I guess I want to look good losing. To that end, son Tom, the guitar maker, is making me a rather elegant ammo box from walnut. I like the way the gun came out so, now, all I gotta do is make it shoot.
Right now it's humid enough outside that the air is almost a solid. Typical of Michigan in June. I don't know how 2015 reacts to that but I'm about to find out. I hand rubbed another coat of finish on the gun last week but it's dry enough now to shoot. Gotta do it... match Saturday.