I have plenty of 45 cases and fineshot, and could.easily use a bunch for shot shells. I have never tried it. Do you have an internet site that shows the process, or is it something you developed yourself? Sounds like funny
I made threads years ago but the photos were uploaded to photo bucket and they are holding them hostage, making the threads less than useful.
I modified an existing die when I first started. Form the case first, then I machined a bolt/cup to push the over shot card down as I crimped the mouth.
Use a gasket punch to make the over shot cards. Clear plastic allows you to see the shot, if you play with different sizes. I prefer #12.
My 45 ACP shot rounds use cut down .410 wads and have much better patterns than the capsules deliver.
Even made some long ones for revolvers.
I got a little smarter on that little one on the left above. It’s a .380 ACP shotshell made from .223 brass. Instead of working over an old die, I machined an insert that could be dropped into a Lee powder die, much, much, easier.
Dump out their insert (right) and drop in mine (left), the washers are just shims because the piece of metal I found at the saw was a bit short.
It’s not hardened but still makes a good looking round. They do become a bit more defined once fired (right).
They also all remain functional as semiautos.
45
380
I have also used the cases for 9mm, just back the .380 die out a little so the “shoulder” is in the proper location.