Interesting search term

Shotgun on top with 22 on bottom.

Honestly I don't know of any firearm like that. Most combo guns will have the shotgun barrel on the bottom with the rifle barrel on top. I point you towards the Savage Model 24, the Springfield M6 Scout and I've seen a Belgium made gun, not a FN gun, that has a .22 on top and a .410 below but for the life of me I cannot remember who made it. It's been over 20 years since I've seen it. If you don't need it to be a double barrel there is the Rossi Matched Pair rifle shotgun combo of which I have one with a 20 ga barrel and a .22 barrel. I paid $169.99 for it brand new with a black nylon carrying case. My kids and I enjoy shooting it. If you go to the link I put in for the Savage it will show you about combo guns with multiple barrel configurations. But I personally don't know about them other than what I have posted plus I many years ago shot a Drilling which they talk about in the Combination Gun entry on Wikipedia. The one I shot had British makers and proof marks and was an S/S .450 Nitro with a .303 British underneath. I loved that gun, but the recoil with the .450 Nitro was a bit stiff for me.

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