Well, it is not exactly a sidelever Martini or Peabody. The Norwegian name for the rifle is Tennstempel. And as you can see from these diagrams how the breechblock more or less "floats" in the action. Where the Martini and the Peabody have a pin at the back restricting there movement. Please also note in the diagram how the block enters the rear of the chamber upon closing. Something like a cork in a bottle


Tennstempel....



Peabody....