Guys,
I actually have a Thieme & Schlegelmilch, Nimrod 12 Ga SxS. There are a couple of variations. Mine is the one with the Sidelocks. The difference in the Sidelock for the Thieme & Schlegelmilch, is that the hammer pins and action pieces fit into holes in the sideplates, but also are fitted into the action frame it self. This gives a solid two point support. The springs for the hammer strikers are actually mounted into the action body. The cocking rods / arms are much the same as a traditional sidelock. There is also a standard boxlock action Thieme & Schlegelmilch, Nimrod. The big inovation is the action frame. The matiing of the barrels and the frame are not with a flat water table to a flat frame. The flat of the frame on a traditional gun is actually stepped down in a wide lowere knotch in the frame just in from of the standing Breech. This corresponds to a fitting plate of steel on the barrel lumps. I suspect that all of this notch with fitting steel prevents the strain of pressure on the action hing pin and the green cross bolt.
The NIMROD part is a trade name for hunting arms from Thieme & Schlegelmilch as a maker.
I have seen drillings, double rifles and the SXS shotguns in both the side lock and the boxlock. Mine is high grade wood, light engraving. Very light frame and barrels. It weights in at about 6 pounds. I love it for bird hunting and shoot it alot. It was a 2 1/2" chamber gun, but I had the forcing cones lengthened and shoot lighter loads in it. Great gun. Interesting and different.