Hello 93x66mm,
Thanks for the reply.

The "gizmo" as you call it, was made from a brass 6-point "crimp-starter" insert from an old MEC 12ga shot-shell reloader. You could swap inserts to change from 6-point to 8-point crimps. Today they are made of plastic, but in the old days they were hardened brass. I had one laying around and got creative. Although they are no longer available, I see a few for sale on eBay for around $25.

I cut it off, and to keep everything in-lined, I soldered in into a brass sleeve that is a snug slip fit over the brass case. I then opened up the center to allow clearance for the bullet's nose. I made a another tool that matches the shape of the bullet's nose, that presses the bullet down into the case as the crimp is being formed. It weighs about a quarter pound so all it takes is a couple of thumps with the palm of your hand to do the crimp. The pictures below tell the story.

As far as my loading recipe goes, I'm using UNIQUE powder with Winchester brass cases. ?? grains of powder, covered with a tight fitting 1/8" thick card cut with the punch that came with the rifle, followed by five (5) 1/2" thick 12ga. fiber wads, with another 1/8" thick card under the bullet. Bullet was lightly finger lubed. I'm not going to publish powder weight until I have a chance to test it later today. Also, I'll first test the loads in a "cheap" modern 12ga double barrel shotgun to be on the safe side. When I dive into uncharted waters like this, (something I find myself doing quite often) I always try to be conservative. I don't want to harm this treasure.

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