Looks good so far!! My father made some of those back in the 50's they almost look professionally done, pretty amazing stuff. I found a ring made from a 64 Kennedy Half once...wasn't that great of quality tho.
My father says he used to make them. He says all you do is take a silver quarter and hold it with the tip of your fingers in the center of the coin, then with a spoon tap on the edge of the coin flat with the spoon and rotate the coin and repeat until the ring is finished. Once the ring is down to the right size drill a hole in the center and widen then polish.
Have fun making them I think i will try it once or twice.
use a small drill with caution to make the hole and then finish out drilling the inside with a dremel tool or something likewise. Loking forward to seeing your finished project! :-)