If you go to the Hogdon site listed up in the "Mfs links" stickies on this forum, they'll give you the load data they've been successfful with. And it's FREE! My books are all packed up now or I'd PM you. But with Clays, I think you'll find tht you ccan't get much over 730 fps SAFELY, nice accurate mid-range target load that should cycle.
I've never used it but Clays (Yup, the Hogdon stuff) is supposed to work very well in the 45 acp for target work.
I once loaded up some 9mm with light Unique loads, most accurate 9mm loads I or anyone else ever saw, but they wouldn't cycle, Colts, Lugers, Smiths, Brownings or anything else known to my club. Dirtier than mud too, being Unique but Boy were they accurate. Turned all semi-autos into straight pulls was the only serious drawback..
I think at 650 fps you'ld have a similar experience. But the Clays would be cleaner burning.
And you're right a pound of powder would easily do your thousand empties, with a lot left over.
Extra care to avoid double charging is called for, Ka-BOOM is such an ugly noise.
Thanks for fixing the powder measurement.
Regards,