Thanks Trailboss. I belonged to that forum many years ago but have not been there for a long time.
Good note on smashing them to see if the coating stays. Shows that they can be sized after coating/curing.
My first #429303 mould was an Ohaus 4-cavity mould. I only shot them in the m29 4". At some point, I re-bored every cavity to cast straight sided bullets for paper patching for my .45 buffalo rifles.
Later, I lamented doing that as the #303 bullet was very accurate. A couple years ago, a friend gave me all his mould blocks as he was finished with casting, most of which were unused and amongst them was a new in the box DC Lyman mould for the #429303 bullet.
What do the .50's weigh?