Obviously watched the vid,some parts twice. My "take" on it was that he was loading the charge of powder,not really knowing the weight of the pellets or buck. Like rifle and pistol,powder weight goes up,bullet weight comes down. Could be that this was just for the vid.
Wondering also what powder would be used in building a "mini shell". Faster,slower,the same,etc.
The vid was a "show and tell. But if it were me that was loading these shells,I would have a "system" of prep'ing everything (cutting to size) ,then put powder in and a felt spacer,then actually weigh the pellets and even the slug to make sure everything was consistent. I would do the same thing,the same way,everytime.
I also would shoot a few in a single shot to check for pressure and extraction/ejection. Also for pattern at what range. I would be looking for a more open pattern than the Aguilla.
I might also try a duplex or even a triplex load. Checking closely for the over all weight of pellets.
For me - -> a load of "BB" and #6 would be good. Possibly all #4 shot. It would be fun to expierament.
If you give this a try,let us know how it goes. --- SAWMAN
ADDED: Wad pressure is another concern. I loaded thousands of 12 and 20ga on a MEC Sizemaster over the years. Wad pressure would have a big effect on pattern density. Possibly does not matter with the mini shells.
I use the minishells in my KSG and they work great , never a problem, but i have also read they do not work well in all pumps and not at all in semi autos's.