We hope a company will be making our modeled 12ga sabots
soon, this fall, to deliver to reloaders and suppliers.. 
We also got first part of funds collected for the initial big run
for our 585HE long cases being made. Sending in bunch
this week, and need more to make run bigger For more info
if your interested contact me.
 We, others, and 'VdoMemorie' on the Cast Bullet forums 
and Shotgun World are experimenting with  58cal Minie slugs and
 58cal round balls in 20ga wadcups, and find it is away to slug 
 load your 20ga economically. You can use 20ga Commander wad and
also  shorter "sporting 20 short" wad from BPI. I cut bottom off of
commander and use  felt wads and 20ga obturator seal with .575"
470gr minie slug and got 4" group at 30 yds, with smooth barrel.
That is with heavy thick,smooth barrel I put  in CBC below.
Here is picture of the CBC break action that I mono-blocked in smooth
super heavy, thick 20ga barrel..30" long, chambered for 3.5" cases.
Works  great with 3.5" plastic or brass cases.
Here is picture of the 1887 WIn with  my 585HE in it. I put in a 
heavy barrel and different kind of extractor  Barrel is 28"..
I like putting my 585HE in all the old style of guns, just
to show all the uses the case has.
I found supply of super  long bmg cases to make my 700HE Long cases.
It is 4.27" long and holds over 370 gr ball powder, 1000gr at 3400 plus.
I have it in my Vulcan BMG bolt action and I just got one done  in
a MRC PH bolt gun, in picture below...Ed