danish Jaeger rifle M 1791/48 so a former flintlock transformed to percussion priming
http://www.lauritz.com/da/auktion/dansk-jaegerriffel-m-1791-1848/i4231153/#

love this old Jaeger rifles, it the service rilfe for a hunter

if you looking for big gauge muzzle loading fowler the french market have a lot of such stuff

8 ga. 94 cm barrel, 132cm oal

http://www.naturabuy.fr/CANARDIERE-A-PERCUSSION-CAL-8-item-2895409.html