There are a few where the barrel is easily removed almost halving the length of the rifle, examples like the Webley Hawk and Hammerli X2.
Baz
Somehow just removing the barrel doesn't seem 'ingenious' enough. The action on this example is a very clever little piece of 'gunsmithing art'...
...but can't think of many (any?) that fall into a true springer TDR category.