A image of the underside of the tubeset might garner a date range. It is an eccentric breech but I believe Central-Feuer/Fire and just a paper hull cartridge, which may be similar to the below:
Cheers,
Raimey
rse
Thank you for the links.
It is most definitely NOT a paper hull 16 gauge. There is no modern chamber. The images I've seen for similar era appear to be a brass base with an old style wrapped paper cartridge, tied at the front with string.
The small recess shown is all there is as far as what we'd consider a chamber.
