I don't have a picture of an altered Krag with part of the magazine removed and replaced with a simple 'screwed on plate', but, I know I've seen such a thing.

Attached are photos of a "Rifleman" How-To-Article, that shows how to make a 'thin' magazine-gate.

Also, attached is a photo showing a KCA Member's Krag, where the receiver was thinned and the magazine opening was covered by the replacement stock. This conversion required the cartridges to be 'backed into' the feed opening.   

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