They had one. The 44 Carbine. Well...sorta. But not rimfire. It was the size and shape of one. The one I had was "cursed" right out of the box. First thing, it had to go back to Ruger because it was a "single shot". Ruger fixed it and sent it back.
Second, no matter what I put in it for ammo, that thing just would not kill anything. I could get 3" groups at 50 yards - not great but it should have been adequate in the thick woods I hunted in (and I do not shoot through bushes) Easy broadside shots at deer were clean misses.
I put a scope on it. I put aperture sights on it. I even took up reloading, hoping to find the "right" load for it. That gun would not kill anything. One day, I was lined up on a fat woodchuck about 20 feet from me. I was prone and the gun was well supported. I slowly squeezed the trigger. Clean miss!!!! (Saw it several more times after that - not a scratch)
That was that! I sold that gun off and got a Marlin 30-30 and had no trouble getting venison, woodchucks, and squirrels after that.