I have a Model 17-5 that never shot as well as I thought it should, although I mostly blamed myself, not the gun. Then it got much worse, so I let a more experienced friend try it, and for him too, the holes were splattered all over - no group.
I'll skip over a lot of miscellaneous stuff, and get right to where I'm at now.
First discovery - the cylinder is NOT locked in place by the cylinder lock. With the hammer back, ready to shoot, I can place my hand on the cylinder and rotate it back and forth. Apparently the cylinder lock under the cylinder is supposed to fit into the opening on the cylinder, and lock things in place.
Second discovery - if I swing out the cylinder, and put my hand over the cylinder lock, it sort of felt like I could slide it back and forth left to right. After a lot of trial and error, I no longer think it is SLIDING back and forth - it's more like it "pivots" to one side or another, which is what is allowing the cylinder to turn one way or another. I suspect this is counter-productive in terms of shooting well.
I don't remember what holds the cylinder lock in place. Maybe it's broken, or maybe it's worn out, or maybe something is coming loose.
I will post a photo of what it looks like, but I don't know how to show why I think it is broken, or coming loose. All I can say is I can hold the cylinder stop in my hands, and "rock it" to the left or right, moving it as I do so, meaning the cylinder can rotate to either side and back quite a bit. If the cylinder stop was held firmly in place, this issue would be solved.
I should add that I haven't decided yet if I should take it apart, or take it to my gunsmith. Probably the latter, as he will "feel" the problem and probably immediately know what's needed......
I'll skip over a lot of miscellaneous stuff, and get right to where I'm at now.
First discovery - the cylinder is NOT locked in place by the cylinder lock. With the hammer back, ready to shoot, I can place my hand on the cylinder and rotate it back and forth. Apparently the cylinder lock under the cylinder is supposed to fit into the opening on the cylinder, and lock things in place.
Second discovery - if I swing out the cylinder, and put my hand over the cylinder lock, it sort of felt like I could slide it back and forth left to right. After a lot of trial and error, I no longer think it is SLIDING back and forth - it's more like it "pivots" to one side or another, which is what is allowing the cylinder to turn one way or another. I suspect this is counter-productive in terms of shooting well.

I don't remember what holds the cylinder lock in place. Maybe it's broken, or maybe it's worn out, or maybe something is coming loose.
I will post a photo of what it looks like, but I don't know how to show why I think it is broken, or coming loose. All I can say is I can hold the cylinder stop in my hands, and "rock it" to the left or right, moving it as I do so, meaning the cylinder can rotate to either side and back quite a bit. If the cylinder stop was held firmly in place, this issue would be solved.
I should add that I haven't decided yet if I should take it apart, or take it to my gunsmith. Probably the latter, as he will "feel" the problem and probably immediately know what's needed......