Gas ring eliminated, for one thing.
Howdy Again
Not quite. Uberti did not eliminate the gas ring or gas collar. But they did greatly reduce it in length.
This is a real Schofield cylinder. Notice the collar at the front of the cylinder. This is a separate part, press fit into the cylinder. It stands roughly .170 proud of the front face of the cylinder. Notice there is space inside the collar around the ejector rod and spring.
This is how it fits together. The extractor rod and spring slide inside the cylinder arbor.
The gas collar remains outside the arbor.
When completely assembled, the collar butts up against the lower part of the barrel. This means the barrel/ cylinder gap is approximately .170 horizontally away from the front of the collar. When the revolver is fired, Black Powder fouling blasted out of the barrel/cylinder gap is prevented from being blasted onto the cylinder arbor. The cylinder collar shields the arbor from the fouling. With the arbor protected this way, fouling does not build up on the arbor and the cylinder is able to remain rotating without binding. Contrary to popular belief, it is not the fouling building up on the cylinder face that causes a revolver fired with Black Powder to bind up, it is the fouling that gets down onto the arbor. Notice too, the outside of the arbor has a helical groove running around it. This is there for clearance. Any fouling that finds its way down onto the arbor will settle in the helical groove, and be less likely to bind the cylinder.
Here is the cylinder from a New Model Number Three.
And here is the cylinder from a 44 Double Action. All of the S&W Top Breaks had a similar cylinder construction. They all had horizontal separation from the barrel/cylinder gap to the front of the collar. After all, they were designed in the Black Powder era, and they shot it beautifully. When I use my New Model Number Threes in a CAS match, I can shoot them all day long without the cylinder binding up. Of course, I use bullets that carry a large amount of Black Powder compatible lube on them, to keep the fouling in the bore soft.
Here is what Uberti did. They lengthened the cylinder enough to accommodate longer cartridges such as 45 Colt, but did not lengthen the cylinder window in the frame a similar amount. The gas collar got shortened. Not eliminated, but shortened.
When the gun is assembled, there is not enough horizontal displacement to prevent fouling blasted out of the barrel/cylinder gap from making its way onto the cylinder arbor. This gun has not been fully assembled, hence the gap at the front of the collar. But you get the idea.
When S&W went to a 1 9/16" cylinder for the 44-40 and 38-40 versions of the New Model Number Three, and 44 Double Action, they also lengthened the frame to accomodate the longer cylinder and did not mess with the gas collar.
Most revolvers designed in the Black Powder era used the same principal. On the left in this photo is an Uberti Cattleman cylinder with its removable cylinder bushing. On the right is a Colt cylinder and bushing.
On the left is the Uberti cylinder with the bushing in position, on the right is the Colt cylinder and bushing. In the middle is a Ruger Vaquero cylinder. The bushing is an integral part of the Ruger cylinder.
With the bushing in place in the Colt cylinder, there is enough horizontal separation from the barrel/cylinder gap to the front of the bushing to prevent fouling being blasted onto the cylinder pin.
The Ruger has even more horizontal separation than a Colt, and they shoot Black Powder beautifully, without any binding.
One design that lacked a bushing on the cylinder was the 1858 Remington Cap & Ball revolver. On the left is a cartridge conversion cylinder, on the right is a C&B cylinder.
There is no horizontal separation from the barrel/cylinder gap to the front of the cylinder, so fouling builds up rapidly on the cylinder pin. In my experience this design tends to bind up quickly with BP fouling.
Incidentally, I do not own a S&W Schofield Model of 2000, nor have I shot one. But I have examined a few, and they have a short gas collar much like the Uberti. Everything I have read is they do not shoot Black Powder well. Why S&W chose to shorten the bushing I do not know, because they are chambered for the shorter 45 Schofield round. Maybe they just did not think anybody would want to shoot Black Powder out of them. Another question for my friend.