Well,
I will have another test today. After I gave it a little thought, and having the beautiful H&G #503 mold, I thought I would give it another try only with this powder.
I was using the "new rave" powder, Lil' Gun for my previous trials with lead bullets and just couldn't get the accuracy I knew was possible from this firearm.
I spoke with the Hodgdon tech about this too and he assured me that it would burn WAY too hot to work well on a plain based bullet. I wonder if that was the reason for my poor accuracy previously, don't know yet. If the accuracy turns out to be OK today, I am going to really play with that bullet and powder. If it doesn't I may have a mold for sale!
This mold is bringing upwards of $200 on ebay and that would get me a long way towards an NEI or other mold that would cast a tad bigger.
Wish me the best!