Before you might do something you can't undo, have you used wheelbearing grease on the grooves for the cylinder pin ? I grease mine up really well. The cylinder sort of 'floats' on the grease. The grooves on the cylinder pin should be loaded with grease.
Next I would check the frame itself. Take the revolver apart and check for clearence for the pawl hand inside the recoil shield. That is what rotates the cylinder. I grease that up pretty well also to keep fouling from binding it up. Then check the hammer at the point it rotates and make sure it is lubed also.
Check the cylinder lock and make sure fouling hasn't held that up or retarded it's function.
Last I would check the springs and make sure they are tight and perform the way they are supposed to. If the revolver is really old and has seen a lot of use, you might consider changing the trigger/cylinder lock spring. Good places to look again and don't cost a thing. The grease I use is Sta-lube just for your info.
After you clean the revolver up, use a feeler gauge to check the clearences for the cylinder and forcing cone for each chamber. If you have a high spot, mark it with chalk or something so you can go back to it. Take care of the high spot with a stone. Check the timing, rotation and lock-up of the cylinder. Look for excessive and abnormal drag marks on the cylinder. You might need to swap out the cylinder lock. If you did, I would still change springs to go with the new part.
When you go to the range, before you load check the clearence again at the cylinder face. When the weapon locks up again take note of the cylinder position and mark it with nail polish or something like that, Dye-chem, crayon, anything. Pull the weapon apart and give it a quick clean job on the cylinder face and forcing cone. Check the wedge and mark that as well so it get returned to the same position. Start over and see if it happens again at the same spot.
Check to see what is in the fouling also and try to eliminate that in your loading process if possible. It might be something so simple, but so frustrating. It might even be something as simple as changing the powder to a different granulation. :thumbsup:
Don't give up.