Here are a few things that you can try to sort out the cause.

First, use a small diameter dowel, a pencil, or anything similar as a probe to determing if you may have a sqib lodged between the cylinder and barrel. If you do have a sqib jamming the cylinder you'll have to drive it back into the chamber in the cylinder to free the cylinder. For doing this my preference is for a 5/16 inch diameter hardwood dowel in either white oak or hard maple. Also, keep in mind that a squib means the primer for that chamber has fired so you are safe driving the bullet back into the cylinder, however don't get stupid and try to hammer the bullet back in one hard blow because you could bend the frame. Instead take your time and knock it back in small increments with a lighter strike of the hammer.

Second, the cylinder stop is spring loaded and can be pushed out of the notch in the cylinder. My preferred implement for doing this is a basic business card because they are usually on hand and no marring in regards to finish. Slide the business card btween the frame and cylinder in a front to rear motion and the cylinder stop will be driven out of engagement with the cylinder. Leave it in place and you can spin the cylinder freely in the frame if it's not jammed. Means that tightening the ejector rod is rather simple, use a fingernail to jam the ejector rod at the knurling and rotate the cylinder until it's tight enough allow the cylinder to open.

Third area to look at is at the firing pin and bushing. As previously noted a blown out primer can jam up a cylinder, however in 38 spl. that is a relatively rare occurance. One thing that may not be that rare is with the gun that feature frame mounted firing pins. Some ammos are foul enough shooting to cause the frame mounted firing pins to "stick" in the frame. In addition, extensive dry firing practice without the use of snap caps could cause the small spring that returns the firing pin to fail, leaving the firing pin stuck forward in the primer dimple. BTW, I've been there done that and it's why I now avoid using WWB ammo, 5 boxes of that crud fouled up my 610 enough to jam the firing pin forward. What has worked for me to free up a stuck firing pin was simply rocking the cylinder left and right using a rather gentle amount of force. Took me a bit under a minute but eventually that stuck firing pin popped back into the frame and I could unload the 610 and take it home for a good cleaning. BTW, I was rather surprized and how much crud was caked into the recess for the firing pin in the frame. As for the cause, I suspect a combination of powder fouling and the mis-application of gun oil in the area of the firing pin. The S&W manual does suggest an occasional drop of oil in this area and I now believe that doing this is a mistake. I'll also note that my 610 had at least 3000 rounds on it when the firing pin got stuck so it was due for a good cleaning. However, it's one somewhat minor dis-advantage of the frame mounted firing pins, when they get stuck you can't pull them out by simply cocking the hammer.

Now for a final note. That is that more force is rarely the solution for issues like this. While a gentle approach does take longer it usually results in less damage to the gun. So, take your time and work gently, the end result is usually just as successful and a lot less damaging.

Thank you for posting that. I had a nearly identical situation as described in the OP and this suggestion fixed it in about three seconds flat. Bravo,scooter123!

Had a similar issue this weekend with a 44 mag, the bullet was stuck between the cylinder and the barrel, 2 sharp taps on a dowel down the barrel... Voila.

thewelshm

basically what scooter said above, and we use a plastic "wedge" ( thin shim) to put into the ejector slot ( the open area under the barrel that the ejector sits in recessed) easier to to this than a finger nail or any "tools" that can and will mar ,scratch the ejector rod...when it is wedged in there, turn the "loose" cylinder in whatever direction your model may be right , maybe left, till the rod screws back in enough to open , other wise you can sometime just "pop" the assembly open and out on your knee ( don't hurt yourself)...if the gun was "unloaded" you can simply pull back the hammer a bit to lower the cylinder stop ( bolt)...to "loosen" turn, the cylinder........

__________________
dan
NRA Benefactor,PMA