Howdy
This new design was introduced about three years ago. As the older Cattlemen with a fixed firing pin in the hammer are bought up, the newer model, with the floating firing pin will be the only type Uberti is shipping.
I got a chance to shoot a couple of them a couple of years ago. One worked fine, the other was a bit problematic. If the trigger was yanked with authority, it fired every time. However the owner, a small woman, was used to squeezing the triggers on her revolvers very slowly, like a good target shooter, until the gun fired. She kept getting misfires with her trigger technique. I tried her technique of a slow pull, increasing pressure slightly until the hammer fell, and sure enough I go a few failures to fire too.
I suspected there was something inside, perhaps a burr, preventing the firing pin from extending all the way when the trigger was pulled. Seeing as it was not my revolver, I did not get a chance to tear it apart, so do not know what the final resolution was.