I might try that but would note that the plate is made to fit in the black bowl ID taper.
In actual practice for me, the plate in the black pan is quite adequate until there is a high volume of 380 causing congestion, never happening to me so far. Removing the aluminum plate to get the 380 off the black plate has never been a problem. I think they state it as too dramatic. If I wanted the few 380s to fall through, I could use the blue or yellow bowl, but the black bowl is the exact size to catch 380 and let 32 and 22 fall through. I don't use a bucket under the bowls but I could, if it was a mess of dirt and who knows what.Ummm, not exactly.
http://www.shellsorter.com/products/shell-sorter-380-plate
This 380 ACP adapter plate allows reloaders to easily separate 380 ACP and small brass from 9mm Luger. To use this plate, sort all of your brass as normally through the Shell Sorter™ 3pc set. The contents of the black pan will contain 9mm and 380 brass. Set the 380 plate inside either the blue or yellow Shell Sorter™ pan. Sort the contents of the black pan through the plate, 380 will fall through both the plate as well as the blue or yellow pan, 9mm remains on top. Do not use the black pan with the 380 plate as the 380 brass will get trapped between the plate and the black pan, where you will frequently need to remove the plate to get the brass out
I have the sorting insert for .380's and it's not worth the money. In fact, I do better hand sorting, or using my Berry's brass sorter, than I do with the bucket sorting trays. There's not enough room between the three inserts to make it usable, and the Berry's is adjustable and faster to use.
Here's the link: https://www.berrysmfg.com/item/rotary-brass-sorter
Hope this helps.
Fred
Here is what I do