If 'twas me messing with clay, I'd be thinking more along the lines of the old "ballettes," however it's spelled.
I'd roll out a sheet roughly the same thickness as ball diameter, then use some kind of cookie cutter, also ball diameter. Likely have to do a little experimenting with that since I'm pretty sure clay shrinks when it dries, and certainly when fired in a kiln if you want to go that far in hardening them.
My best guess is that they wont need to be kilned if you're shooting low vel for plinking and small game. I'm betting they'd be darned accurate once you worked out the kinks.
I have just one insight on small game use. Some of you might be geezerly enough to recall the old "gallery" 22 loads, basically short-shorts with clay bullets at low vel intended for indoor use. About 40 years ago I got a whole bunch for darned near free (still have a few of those boxes, as a matter of fact). Didn't like the noise for indoors, but they were a hoot outdoors.
Got inspired by rabbits in the garden and tried them on head shots. Absolutely decapitated the rabbits. No other way to say it- those clay bullets exploded on impact, kind like stuffing a grenade up a rabbit nose.
A 50 cal clay bullet? DO NOT take a body shot! :shocked2: