wow you have really put some work into this.
I saw while looking in to this today that a few guys have taken 357 handi rifles an chambered them to 357 max. that would be a good way to find a use for your brass cheap an fun . I like those guns wish they made a pistol.
ill have to look you up for a chamber if I ever get any were on this. But Im digging the using 223 brass for some thing. im aftad to geep reloading it in my 223. a few split necks an id hate to rupture a case or get one stuck on a anual prairie dog trip 700 miles from home. I was thinging of making 7.62x25 out of it but the ammo is stll reeasonable surpluss ( duble from three years ago) Im likeing a 9mm deal better.
I was thinking I might be able to take my 6mm bench reamer when I get it an piolet it for a 9mm or 357, 358 bore an make a 357 bench rest chamber an then just neck an throat it. that would give you a lot more power tha a 223 case an culd use 308 win cut down or 6mmbr lupia bras blow out. there wil be a 30 br for sure if i can get the 6mm shooting an feeding.; that would give a real better than 30-30 win round on the platform. ont thing at a time. I got so many dies reamers, brass, barrels an stuff coming in these days I cant keep it straight my living room looks like a Iraq weapons factory on crack.