I collect Eurpoean double rifles and German Drillings, and have figured out that there's a fairly good way to convert any decent double shotgun to a double rifle, using some technology that's been generally used only by the Germans in their drillings. These are, of course, a three barrel shotgun/rifle combination. Most commonly they are double 16 gauge over either 7x57 Mauser or 9.2x72R. The thing is that licencing in Germany makes it hard to own multiple firearms, so very often a Drilling is complemented by a device known as an Einsteklauf. These are *very* good barrel inserts, that are adjustable for regulation, and when slid into a shotgun barrel convert it to any of dozens of rifle calibers. Unlike the common inserts we see here, they lock into the bore with a tool that opens up a locking foot on the device that wedges it into the chamber, are adjustable for regulation (so they shoot to the same point of aim as the rifle barrel in the Drilling), and most uniquely they also use the existing extractor to mechanically drive another extractor so when you open the Drilling, you extract the cartridge from the device. They come in both short and long versions, the short being about 10 inches long and the long versions being full barrel length.
Using a pair of these, you can convert any double barrel shotgun to a double rifle. You can run cartridges right up thru the .30-06 class or larger, and as small as .22 (generally in Germany .22 magnum is used). They are not cheap, but a good shotgun with sights added and two adapters will still cost far less than any double rifle.
Truthfully, when you start looking at these, I hope you are drawn to the utility of a Drilling, and get interested in them. My favorite is a Sauer in double 16 over 8x57JRS. That alone is great: The left barrel shoots to the same point of aim with Brenneke slugs as does the rifle barrel. I stick a .22 mag einsteklauf in the right barrel and I have .22, shotgun, and 8mm rifle all in one with a claw-mount scope that snaps off in a moment. Then there's a 9.2x74 adapter for the left barrel that gives me a cartridge suitable for any African game I would ever care to shoot. Contemplate these.
Google "einsteklauf" and see what you come up with. Most websites will be in German, but are self explainatory. There are several makers at different price points. Good quality short ones are available used in the $300 range with new top quality long versions worth up to $2000 each. These aren't your el-cheapo inserts.
16 gauge is the most common guage these are made for, but there are many for both 12 and 20 as well. The 16 is likely going to offer the best balance though, if you want to assemble a quality setup.
The biggest thing to solve when converting a shotgun to a double rifle is regulating the barrels to shoot to point of aim. The adjustments inherant in an einsteklauf make this a simple task.
Willie
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