S&W ejector rod runout

[RA40]

The ejector rod on the 686 has some runout after loosening and having the cylinder opened up. Ordered a new one to swap out. Was quite a bummer because the revolver has a glass bead finish and it took a bit of finessing to match the new ejector rod finish to the frame. Then to screw it on and find it had more runout than the bent one was

Edit Didn't put the dial gauge to the rod so just did that. Runout is coming in at about .001" -0015". Something else is causing the ejector rod to appear bent.

Suggestions, thoughts?

 

[shooter1niner]

(.001" - .0015") one to one and one half thousandths is bad?

 

[BBBBill]

Runout can be removed, but it usually requires some semi expensive equipment to do it without pulling your hair out. Ron Power makes a jig for that.

 

[JohnKSa]

Something else is causing the ejector rod to appear bent.

I take it you installed this one because you thought the last one was bent. This one also seems bent when installed but is actually straight.

The ejector rod screws onto a thin rod that runs through the cylinder. Sounds like that's what's actually bent.

 

[RA40]

Yes as you mention about the ejector rod. I'll take a look at that center pin. Seems weird that that thin pin could be the cause but it makes sense to check it. The cylinder does not bind and actuates equally for the six positions as far as my finger can detect. Some thoughts were possibly the extractor rod collar or the yoke has high spot that causes some deflection.

I take it you installed this one because you thought the last one was bent. This one also seems bent when installed but is actually straight.

The ejector rod screws onto a thin rod that runs through the cylinder. Sounds like that's what's actually bent.

 

[beag_nut]

(.001" - .0015") one to one and one half thousandths is bad?

Perhaps a decimal point was misplaced? If not, this discussion is moot.

 

[JohnKSa]

Perhaps a decimal point was misplaced?

That's the puzzle. The rod is straight but when installed it wobbles when the cylinder is turned.

My theory is that the thin rod it threads onto is bent.

 

[straightshooterjake]

I am not sure if I am correctly understanding the problem in this thread. Is the issue that the ejector rod itself is straight, but when the ejector rod is tightened into the cylinder, then the ejector rod has run-out when the cylinder is turned? In other words, the entire cylinder and ejector rod assembly is not trued up even though each of the components appears OK?

If this is the issue, then I do not know the exact cause, but I have seen it before, and I don't think it is all that rare. My suspicion is that the threads on one of the parts are not cut true to the centerline. In one case where this happened, I examined the extractor rod collar very carefully, and it seemed perfectly even.

The solution I used for this issue was to tighten the extractor rod and then true up the whole cylinder assembly by carefully bending the extractor rod. I believe this is how Ron Power's jig works, but I got by with a makeshift jig. I also found that if the extractor rod is loosened and retightened, then it might need to be trued up again.

 

[RA40]

straightshooterjake has it.

The ejector rod when put up against the dial indicator measures from .001" -.0015". When screwed into the extractor assembly, cylinder placed into the yoke and spun, the ejector rod shows runout. Mine spins nearly the same as in Larry's video at the 34 seconds mark:


Something within that assembly is off and I'm not sure to what extent this may effect this revolver. In my hands this is the least accurate for me to shoot compared to the other 686 and 66. Later in the week I'll have some time to take the cylinder apart and put the other parts to the dial indicator to check. Wondering if the extractor is the bent piece here and or the threading is slightly off. (?)

 

[RA40]

Runout can be removed, but it usually requires some semi expensive equipment to do it without pulling your hair out. Ron Power makes a jig for that.

Saw one of his videos of this fixture, that is a really nice one!