Thanks for all the insightful comments.
For the present, I'll stay with the load that I'm using in the M1 Carbine, which is 12.0 2400 under the 311359. I hope that it will shoot reasonably well in the revolver, but time will tell. I see little point in having two different loads for a rifle/handgun pair.
NVCurmudgeon is my compadre for shooting excursions (and MANY other activities) and he shoots a .32-20 Marlin. Maybe I'll cadge a few of his loads and try them in the Ruger, too.
The noise level will be interesting to experience, as the only loads I've ever fired in a Ruger .30 were factory-made, and yes, they were obnoxious.
Perfessor, I note your comment on the 6.5" .357. This is one of my "wants" right now for some reason... my favorite dealer has an Old Model (three screw) 6.5" .357 which has had the factory conversion performed on it to make it a transfer-bar action. He does NOT have the original parts. Condition is excellent, price is $400. I'm thinking about it.
With one oddball exception, this is the first time I've owned a rifle/handgun pairing for the same cartridge. The last one was about fifty years ago, and the cartridge was .303 British (I SAID it was an oddball, didn't I???)