Vierling, not Drilling!
Yes they have been made. But they are commonly referred to as Vierling. If you know Deutsch you can understand why.
I first saw one as a 16 year old taking a Hunter Safety course. One of the instructors had one he brought back from Germany. Had two SXS 16 ga shotgun barrels, a centerfire rifle barrel slung in the usual place under the shotgun barrels (can't remember the caliber) and a .22 cal bore drilled through the rib! The .22 was chambered for very short cartridges, shorter than american 22 shorts! They were slightly larger than CB caps, quite popular in Europe and made by a company called Flobert (I think that is the correct spelling).
The owner told me that the 22 was for finishing off wounded game.
The Double Gun Journal has had several articles on vierlings, some with two Shotgun and Two rifle barrels. One I remember had four 410 shotgun barrels!
Lots of neat stuff out there.
Geoff Ross
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