I've used one for a while when I was more active and shooting revolver in ICORE and USPSA, with my S&W 625. You can open the cylinder without any shifting of the gun in your hands. I took it off later; it's annoying any other time.
Pushing forward on the cylinder release (on a S&W ,on a Colt you pull back on it) moves a rod inside the frame that lets the ball detent that holds the cylinder in place in the frame, ( keeping the cylinder and its chambers inline with the barrel/forcing cone) move so that you can then swing the cylinder out to dump out empty shells or fill the charge holes (chambers).
Does save a bit of time in a match, making it easier to find the latch and not shift the hand to have to do so for a reload.
Getting that rebound spring back in most S&W revolvers (without the special tool) can be a bit of a pain..... Wounder if NYECOgunsmith, knows some secret technique to reinstall the rebound spring and slide?? I've done it a number of times, but it's a struggle.
Yes I do know tricks to get it (the rebound spring) back in and for a price I will divulge them!
But if I tell ya, then I have to kill ya...……..it being such a huge trade secret you see...…..involves a bit of grease and some powdered rosin and a small flat bladed screw driver and a bit of practice is all.
Or just make or buy the tool.
If the hand is on the left side of the frame, it will spin the cylinder clockwise, if it is on the right side of the frame, counter clockwise.
Some manufacturers have guns models that spin one way, and other models that spin the opposite direction.
Ruger Double actions rotate clockwise, while their Single Actions rotate Counter Clockwise, for example.
Pretty much every single action cap and ball revolver made will rotate Clockwise, because the port for installing the caps is on the right, probably because 85-90% of the worlds population is right handed I guess, but it's actually easier for a leftie to install caps on a cap and ball using their right hand.
Anyone care to guess WHY Colt chose to make their DA revolver cylinders spin Clock Wise?
When Colt wanted to come out with a DA revolver 100+ years ago, S&W already had a DA revolver and patents on it, to get a patent on their design, Colt had to be significantly different.
One difference was the pull to open cylinder release, the other was the Clockwise rotation of the cylinder, with Colt claiming that the hand being on the LEFT side of the frame as the cylinder was closed, it was a greater guarantee of a solid lockup of the cylinder in the frame window, and of the gun cycling reliably.
At least that's the story I got when attending a Colt factory service training session many moons ago.
Now as for that pesky rebound slide spring...……...
Coat it with a bit of good gun grease, slide it into the rebound slide, then while holding down on the slide and spring with the thumb of the right hand, same as you did when you removed the spring and slide, use a small flat bladed screw driver ( I use my thumb nail on my right hand, when doing a few of them can generally do them one handed on the first try) and pull back on the spring as you push down.
The left end of the spring needs to end up to the right of the little stud.
Or use a small, Philips screwdriver and put it in the center of the open end of the spring and push it to the right, the slots on the Philips will clear the little stud that holds the left end of the spring in place and let you slip it right in.
Or make a tool from a small flat bladed screw driver by taking a Dremel® tool and cut off wheel and grinding a small slot into the tip of the flat blade screwdriver to capture the end coil of the spring.
IF you then heat the screwdriver shank, just immediately behind the flat portion, and bend it into a shallow "S" curve, it will make it easier for you to push back the spring while getting around that little stud.
Or make a tool from a piece of copper coated welding rod.
Or spend the $4.99 and buy the Wheeler Engineering hex screwdriver bit tool for this task.
Remove the spring with a small flat bladed screwdriver or crochet hook.
As for the powdered rosin...…….I was just kidding, was gonna say Eye of Newt, toe of Bat, but fingered you guys would too quickly catch on to that being a joke. The powdered rosin has no use at all in this situation and should be kept way away from the internals of anything, especially guns!
It will really gum up the works in a hurry!
You said in an earlier post, that you would tell me how to get that rebound spring back in, for a price, so what do I owe you? Of the methods you described, I think I'll modify a Philips screw driver. Doh, why didn't I think of that!
Mike, just pass the info along and the debt is paid.
Problem with being old and having a life time of learning behind you is, if you don't pass it along, it dies with you, and there is no telling how much valuable tribal knowledge has been lost over the centuries because someone didn't pass it along.