I was shown a couple of French shotguns today. Side by side. 12-bore. 65 mm chambers.

Boucher.
Made in Saint Etienne.

One shotgun has a left barrel smooth bore. Right barrel has shallow slow twist rifling.

I will try to post some photos.

What would this shotgun be used for? Shot and ball. Shot and cone shaped slugs?

How would shot go through the shallow rifled barrel?