Howdy
I am primarily a S&W guy, so almost all of my Top Breaks are Smiths.
You are talking about 38 S&W and 32 S&W, so we won't talk about the big #3 Top Breaks.
The first thing I will mention is I will not shoot any of my Top Breaks with modern Smokeless ammunition if they were made before about 1905 or so. Many shooters disagree with me over this, and most believe that cartridges such as 38 S&W and 32 S&W are loaded down enough today so they will be safe to shoot in the old pre-1900 days. I don't buy it, so I don't shoot my oldies with modern Smokeless ammo. Unlike Colt, where there is a clear dividing line drawn at 1900 for which guns are safe to shoot with Smokeless and which are not, it is not as well defined with S&W.
You mentioned the Double Action 4th Model. This one left the factory in 1898, so I will not shoot it with modern ammo.
I used to think the Perfecteds were silly. I just could not get into the idea of having to shove the thumbpiece forward simultaneously with lifting the top latch in order to open up the gun. But something about them appealed to me, so now I have three. I think I better stop now. The Perfecteds were the last Top Break design that S&W introduced, they were made from 1909 until 1920. From left to right, these shipped in 1912, 1917, and 1913. I have no reservations about shooting them with modern Smokeless ammo.
Incidentally, the Perfecteds are the only Top Breaks S&W made with the trigger guard integral with the frame. Unlike all the other S&W Top Breaks, the mechanism is basically the same as the modern Hand Ejectors. However they do not have a hammer block in them, so be careful if you load up all the chambers. I'm not saying you should leave the hammer down on an empty chamber, because that would reduce them to a four shooter. They do have a rebounding hammer. But if dropped on the hammer with a round under the hammer, there is always the slim chance something might break and the round under the hammer might fire. This is true of all the S&W Top Breaks.
Lemonsqueezers. The correct name for these is either 38 Safety Hammerless of 32 Safety Hammerless. Lemonsqueezers is just a nickname, owing to the grip safety they had. These are a bit difficult to shoot accurately since they were double action only. However if you squeeze the trigger slowly you will feel the action stiffen just before the gun fires. They were made this way on purpose, the internal hammer does not fall until the trigger pull increases near the end of the travel. In other words, you squeeze the trigger relatively lightly, rotating the cylinder, until you feel some more resistance. Then you give it a bit more pressure and the gun will fire.These were never meant to be target pistols, they were hideaway pocket pistols. However they can be fired fairly accurately once you get used to them. Again, I do not shoot any of mine with modern Smokeless ammo, all of mine were made before 1899. If I had one, the only one I would shoot with modern ammo would be a 38 Safety Hammerless, 5th model, which were made from 1907 until 1940 or a 32 Safety Hammerless 3rd Model which were made from 1909 until 1937.
Iver Johnson
The only Top Break revolver I own that is not a S&W is this Iver Johnson double action only Hammerless model. It is not a lemonsqueezer, it does not have a grip safety.
There are a couple of things you should know about Iver Johnsons. Around the turn of the Century (1900 or so) Iver Johnson completely redesigned their revolver line. Among other things, they started using better steel, so these revolvers could be safely fired with modern Smokeless ammunition. There are three ways to tell the newer, Smokeless Iver Johnsons from the older models.
The little owl on the grips faces backwards.
The hammer spring is a coil spring.
The notches on the cylinder that lock the cylinder in position have a straight hard edge at both the top and bottom.
This is an example of an older Iver Johnson. Notice the little own faces forward. Notice the shape of the cylinder locking notches. There is only one straight, hard edge that the bolt engages, the hand is what prevents the cylinder from rotating backwards when at battery. Not as good a system, and finally, if the grips are removed, the hammer spring is a leaf spring. I am not interested in Iver Johnsons anymore, but if I was, I would not even look twice at one of these older models.
Finally, for many years Iver Johnson had a marketing campaign called Hammer the Hammer. This is because they had an internal transfer bar similar to a modern Ruger. (More properly, Rugers have a transfer bar similar to an Iver Johnson.) I cannot verify whether my Iver Johnson has a transfer bar, I have never taken it apart. But you can see by this advertisement that the gun being struck is one of the older Black Powder models. But like I say, I would only look seriously at one of the newer Smokeless models.
