Paper case and happy with roundball, would likely run with catspaw (short) conical.
(first totally blind-assed guess...)
Straight grip or pistol grip?
What does it weigh?
Jani - I'd poke in there with a chamberCasting and know for sure before I'd buy it.
Figure about three drams powder and a roundball for great deer rifle!
Get photos.
Get chamber and barrel measurements.
I love the 16bore rifles.
They're wonderful.
I own and shoot two such double rifles, have owned others.
If you're not going to buy it, please ping me with the seller's information.
Cheers
Tinker