Got your pm, figured I'd reply here since others might be interested too.

I may have mixed up my facts about the 444 brass - I think I was using cut down 444 for regular loads but don't remember if I had to cut the 444 brass down much or at all for shotshells; my RCBS shotshell die does neck the front of the case down but the neck is sized for the 45 Auto so it isn't very long.
No gas check though; the 45 Auto shotshell dies crimp the case over a thin card wad, which gives better patterns than a gas check over the shot. It works the brass a lot though so I've found it helpful to over-anneal them as you see in the pic. I also use a .410 shot cup like you; I found that to give the best patterns.

[Linked Image]

This is at 10 yards:
[Linked Image]

Last edited by Yondering; 09/16/17.