Well,
I took pictures of my three small bore doubles. I am not sure how they will look, but here goes...

From top to bottom is: J&W Tolley sidelock in .318 WR, a Johann Springer 8X57JR, and the Manton .22 HP.

You can really see the difference in size from the overhead view. I think the side view of them lined up distorts the Manton since it is closest to the camera and looks bigger than it is.

Interestingly, the Tolley is built on a large action for this cartridge, has long barrels and weight to match. I took the Springer elk hunting this year and cannot imagine toting the Tolley over the terrain we covered.

If interested, I can take more detailed pictures of any of the three.