Howdy
To carry the discussion just a bit farther, the reason you get a ring with a Colt Single Action Army, or an old Three Screw Ruger is because the hammer has to go to full cock and then all the way down in order to reset the bolt. Both guns have different mechanisms, but they share the same characteristic that if the hammer is lowered from half cock, the bolt will not reset, so it remains up pressing against the cylinder about halfway between the locking notches. Any subsequent rotation of the cylinder after that will cause the bolt to rub against the cylinder, which causes the ring. Bringing the hammer all the way back locks the bolt in the locking notch on the cylinder, so that when the hammer is lowered the cylinder will not move and the bolt will not rub.
I don't mince words. If somebody does not know how to properly handle an older style single action revolver, I tell them, particularly if it is one of mine. Call it mishandling or improper handling or anything you want, I will instruct you before handing you one of my Colts or Three Screws.
I picked up this Three Screw Blackhawk last year, and clearly somebody did not know how to handle it properly.
This one, on the other hand, has been properly handled for its entire life, over fifty years before I bought it. It really is not very difficult to do.
As far as New Models are concerned, the bolt is SUPPOSED to rise early. That is the way Ruger designed them. Rising early is a safety feature, to make sure the bolt does not skip over the locking notch. An early rising bolt will ALWAYS form a partial ring around the cylinder. I bought this Blackhawk in 1975, and it clearly shows the kind of ring that is typical with a New Model. Notice the ring is only from halfway between each locking notch to the next notch. I would not dream of altering the lockwork to avoid the silly ring.
Now................Double Action revolvers are a completely different type of horse. Generally speaking, the bolt is going to be up when you open the cylinder. So unless you are very careful and rotate the cylinder just far enough to engage the bolt with one of the locking notches as you close the gun, you are going to get a ring. Frankly, it is not worth the effort, unless you intend to sell the gun as unfired.
I buy old Smiths all the time. Some of them are really old. I couldn't care less if they have a ring around the cylinder, it is to be expected.
I also don't give a hoot about carbon rings on the front of the cylinder. To those who do, I always say, once you have enough revolvers you will stop worrying about carbon rings on the front of the cylinder.