Here is picture of the two ball sabot load, using two 58cal balls in a 12ga Accutip style sabot.
Hoping we will have sabot like above for reloading soon, in volume so we can load and test a bunch of these 58cal bullets and slugs. There are soft cast, hard cast, and the heavier jacketed. These all work in my 585HE also. The 440gr hollowbase ones loose in the big box on left measure in at .585" and work great in my 585HE cases.
Part of my 585HEs are smooth barrels guns just for testing the different style guns, and different loads. In the one smooth barreled one I have on BBK action, shooting my 585HE with 440 gr hollowbased Minie slug, we were hitting 8 inch paper plate with them going about 2700 at 30yds. Hollowbased they act like shotgun slug at short ranges.
Will be neat deal to shoot them in 12ga accutip style sabots in rifled 12 gauges and the smoothbore 585HEs with $30 barrels. Here is picture of Pedretti(Beretta style) that came as 10ga. I have monoblocked in 585 barrel. In picture there is 585HE case partly out of chamber. I have extra fairly heavy 10ga barrel also and changes in 2 minutes. And that monoblock break action locks up like a bank vault. Real strong.
And an ultimate big bore from history.