Inherited this rifle, what is it?

It appears to be a 'Jaeger' (hunter) rifle, likely German or Swiss. Without markings, it will be difficult to tell more about it.

PRD1 - mhb - MIke

I can not imagine anyone making such a fine rifle and not putting their name on it.

I have no idea!
But that there is some beautiful craftsmanship.

Germanic gunsmithing in the Colonies was done in the style of back home; Guild required apprenticeship. An apprentice, when ready to 'graduate' produced a 'guild gun' which was unsigned, and submitted it to the Guild for evaluation. If they passed, they could sign the guns they made with their name, and we're a journeyman gunsmith. This could well be a guild gun.
OTOH,

David J Rossman said:

I thought about removing the action from the stock to see if there’s any info underneath, is that a dumb idea?

Click to expand...

Not at all. There could be some identifying marks under the wood.
I'd love to have such a fine piece of American history.

Have you removed the lock? There may be some information there.

What caliber is it and is it rifled or not?

The Jaegers I am familiar with are styled a bit differently on the barrel end of the stock. Basically less ramrod is showing and the lock seems a bit off. Generally Jaegers were 54-62 cal but really they could have been anything. Both smooth bore and rifled were also both traditional.

Either way it is a strongly Germanic gun. My thinking is it is more of a Fowler than a Jeager. Being smooth bore and a larger yet caliber of either .66 or 16 gauge. It is close to either of those and .05” off was not uncommon for caliber diameters.

It is a great example and would be a particularly interesting piece if it was, in fact, a guild gun.

David J Rossman said:

I took the lock and the barrel out of the stock and there aren’t any markings anywhere on gun anywhere with the exception of the single “6” or “9” on the tang at there beach end of the barrel (depending on how you view it).

Click to expand...

Anything under the buttplate?