Thought I would post an update. The 464 is doing great with 8.8 grains Unique/Lee C309-113-RF. This is supposed to be a .32-20 boolit but it loads and shoots like it was made for the .30 WCF. I don't even use a separate flare die when loading, the Lee resizing die opens it up enough for the boolit to slide right in. I do finish with the FCD as I do all my rifle loads.
This rifle and load is more accurate than I can hold, one of a very few centerfire loads I have ever tried that I can just pick up and start shooting offhand and get respectable accuracy like my Henry H001T .22 LR. Previously my 1894 .357 served that role, now I'm not so sure. I was amazed at how well these things penetrate. They have no problem going all the way through a 10" log of somewhat mushy and homogenous wood at 35 yards. The same log has no trouble absorbing .38 Special and 9mm slugs at 7 yards. Should be effective for varmints, on four legs or two if the need arose. Looks like it's mass production time!