It was probably a .410. The lever pushed the barrel forward to load and unload. My first thought was they didn't make the gun in .22, then I got to
doubting myself on that, and I just don't know for sure. I've only seen one gun like it, and a photo of another, and they were shot guns. I also think
there was a very early breech loading rifle that used the same principal of the lever to push the barrel forward, but my hardened arteries aren't letting
enough blood into my brain to allow it to use the recall feature, so I'm at a dead stop there. Perhaps someone else has a better memory.