I read somewhere that the M & H was the only break action revolver that would only eject empties and leave unfired rounds in place. Unlike--say the S & W model 3, which would eject everything whether empty or live.
This allowed one to top off their cylinder after firing only a few rounds.
Yes, in theory they were supposed to work that way. In practice it was not always that simple. The idea is that the gun would only open far enough so that spent rounds would fall free, while live rounds would be retained in the chamber by the bullet. This photo shows the 'extractor ring' at the rear of the frame that pulls the cases out of the chambers by their rims. The problem is it does not grab them by very much.
Take a look at this photo. This is the way it is supposed to be. You don't know how many times I had to set up this photo because the live rounds kept falling out of the gun. What happens is once the gun is opened up far enough for the empties to fall free, the bullets in the live rounds are not very well retained by the chambers. The bullet can slip, because of the clearances, and the rim of the round falls free of the 'extractor ring'. The result is both the empties and the live rounds fall out at the same time. I have had no success with my MHs keeping live rounds in the chambers and extracting spent brass.
With a S&W Model 3, you had two options. With the American, Russian, and Schofield models there was a catch at the bottom of the hinge. If this catch was depressed, the extractor did not rise at all when the gun was opened. You could cherry pick the empties out without disturbing the live rounds. Even when operating the gun normally, it does not automatically 'eject everything whether empty or live.' That is not the way they work. What happens when you open the gun is the extractor rises and extracts the rounds. It does not eject them. When the gun is opened far enough, the extractor rod disengages from its ratchet and a spring yanks the extractor back down into the cylinder. The technique for emptying a Model 3 is to open the gun sharply with enough gusto that the empties are thrown free while the extractor rises. Lying the gun sideways while doing this will allow gravity to help. If you simply open the gun and allow the extactor to pop back down, the rounds will fall back into the chambers, they will not be ejected. If you want to cherry pick the empties and leave the live rounds, all you have to do is open the gun partway so all the rounds are partially extracted. Like this.
I was also recently told by an M & H collector that at one time, one of the American importers approached an Italian manufacturer about producing a replica.
However, they finally scrapped the idea because the pistol was just too complex and expensive to produce to stay within a retail price range that the market could bear.
Consequently, he doubted that an M & H replica would ever see the light of day now.
This rumor has been going around for years. Supposedly Uberti looked into the possibility of recreating the Merwin Hulbert, but backed off because of the complication of the mechanism and the small market. This rumor has been going around for years, but I have seen no actual evidence of it.
What did happen was a few years ago an American company tried to recreate the Merwin Hulbert design. They failed. They never got further than developing a 3D CAD model and creating a few parts. They took deposits for a few years, but finally all the deposits were refunded.
