Unknown dish base front loader

I bought this from somebody but can’t remember who… so can’t find any reference as to what it is, manufacturer, etc.
Would the belt be simply a shoulder for the cartridge to index against or maybe the primer such as a Burnside?
Without an x-ray I suspect it’s a round ball.
Anyone with an idea?

Thanks - Dwight

Bullet diameter: 0.458" (11.63mm)
Overall length: 0.946" (24.30mm)
Case length: 0.749" (19.03mm)
Base diameter: 0.443" (11.25mm)
Mouth diameter: 0.475" (12.07mm)

Hi Dwight, this “.44 Burnside” cartridge was discussed in various issues of The Gun Report dating from 1963 and again in 1979. There were several opinions defending its authenticity but B. R. Lewis considered it was a fake. There is also a pointed bullet variation.