Eric with IV8888 looks at an important part of Scandinavian military arms– the black-painted Norwegian M1774/1841/51 pillar breech musket.
The particular example that Eric has started off as a smoothbore dog lock flintlock in the 18th Century but was converted to percussion caps in 1841. A decade later the gun was updated to the now-forgotten pillar breech design which used the Tamisier conical bullet fired out of a rifled barrel.
This latter variant was replaced by the “kammerlader” or “chamber-loader” underhammer system.
You do know kammerlader, yes? If not, watch the video, Eric touches on that too.