M29

[Giorgio Italy]

Hello everyone
I would need your advice. Do you think something can be done about this problem? As you can see the cylinder crawls on the barrel!
On the back of the barrel I don't think there are any signs of workmanship or burrs. The gap seems correct to me
Thank you
Giorgio

 

[Giorgio Italy]

More photos

 

[pantannojack]

Is the cylinder wobbling on the yoke shaft with excessive end shake while closing?

 

[Giorgio Italy]

It has a longitudinal movement that seems normal to me. I thought about putting a washer in front of the cylinder but it should be a few hundredths of a millimeter and rectified. Where can I find it??
G

 

[PatriotX]

It has a longitudinal movement that seems normal to me. I thought about putting a washer in front of the cylinder but it should be a few hundredths of a millimeter and rectified. Where can I find it??
G

S&W K L N Revolver Shim Kits

This is where I have purchased shims in the past.

 

[Nightowl]

I would expect to find some similar matching scratches on the back of the barrel, which I cannot see in the photos. Those are some pretty deep scratches, not just some rubbing on the back of the barrel.

 

[Smith_586]

So from my experience, all the revolvers I've owned with unfluted cylinders tend to wear more than the ones without? Maybe due to the excess weight. All of them locked up super tight.

 

[Jack Flash]

Was it like that when you got it?

The scratches seem to be more or less evenly distributed, which makes me think it is not wobbling. Since the cylinder gap is within specs, I wonder if the scratches are from overzealous cleaning by a previous owner.

 

[Giorgio Italy]

Thanks for the answers
I'll have to buy a set of those washers!

When I bought it it was already like that and I didn't fire a single shot. Of course, if it is too deep a cleaning, it means that someone has cleaned it with a file. I don't see any streaks on the breech, not even on the edge! It is likely that the cylinder advances the moment the pin touches the recoil shield. When the cylinder is closed there are no longitudinal clearances

G

 

[DT75]

Shimming the front of the cylinder will not help, as the cylinder cannot move any further forward on the yoke regardless if the cylinder is locked in or swung out (assuming the B/C gap in the pics is with the cylinder as far forward it can go).

I would check for play in the yoke throughout it's arc of movement, from open to closed. Then I would remove the yoke screw and remove the yoke/cylinder assembly from the frame and inspect the screw and especially the screw groove on the yoke for (uneven) wear. Theory being that if the yoke has some fore-aft, or even side-to-side play,the cylinder could rub on the barrel when closing the cylinder.

That said, because of the pattern of the scratches and the seemingly lack of marks on the barrel, I'm leaning more to agreeing with other posters above, that this is most likely caused by the previous owners actions somehow.

 

[Retired W4]

With no marks on the rear of the barrel I suppose one explanation could be that the cylinder was originally installed on a different gun. The B/C gap looks pretty straight.

Just curious, but is that an Italian proof mark on the rear face of the cylinder?

 

[DT75]

Just curious, but is that an Italian proof mark on the rear face of the cylinder?

It is a Liege, Belgium proof mark.
Should be one on the frame and barrel as well.

 

[Tinkertech]

Sure looks like file marks to me.

 

[kenjen]

Get a gun blueing marker and go over the marks then shoot it and see if they come back then you will know if you have a end shake problem or not

 

[Nightowl]

Looking at the different direction of the marks and lack of any corresponding indications on the back of the barrel, I have to agree with TinkerTech that they are file marks. I cannot imagine why someone would do that!

That being said, I would make sure that the gun is 100 % in spec, before shooting it.

 

[RT44nut]

The forcing cone looks perfect, maybe too perfect. Could a cracked or damaged edged of a forcing ring have caused this and then the barrel replaced? If it was damaged close to the top, would opening the cylinder, closing the cylinder, and rotating the cylinder cause different arc scratches? Is a stamp or markings under the left grip?

 

[steelslaver]

I suspect it has to much endshake or yoke movement and that it has been opened and closed a lot causing the face of cylinder to rub against the corner of the barrel extension. Look at how shiny the left rear edge of extension is.

Get an automotive feeler gauge from any parts house. With cylinder closed press it all the way back and record the thickness of the largest gauge that will go between face of cylinder and barrel extension. Now press cylinder forward and see how thick of gauge goes. I bet in this case its near zero. The difference if the amount of endshake. You need to have .001-.002 for the cylinder to turn smoothly. NO more.

Also you can see rub marks on the frame where front of yoke has rubbed it closing. So, check to see if the yoke moves back and forth in the frame with the cylinder open. This can be caused by a worn front side plate screw or the button on the end of the pivot shaft of the yoke. The button can be peened back. If this is a newer model withe the tapered slot and the spring loaded ball type screw try replacing the screw

Quit spinning the cylinder and closing it because that is what it looks like someone has done a LOT. That gun hasn't had near enough rounds through it for that to occur. I don't believe it was done with a file as the marks are a bi arced. A file usually makes straight lines and there are no lines at all in center portion

 

[jaymoore]

It is uncommon, but I've seen it from time to time. The marks are generated whilst closing the cylinder. When closed, the endshake is often OK. The pressure to make the marks comes from the center pin spring pushing the works forward. As steelslaver notes, it usually can be traced to wear on the side plate screw and/or the groove in the lower arm of the yoke in the old style assemblies. Once closed there's usually additional support on the yoke surfaces to keep endshake in check.

Sometimes swapping sideplate screws will work. I've also peened the yoke, but that is delicate work. Welding may be an option if replacing parts isn't viable. Having a pile of old but unworn yokes does help.... ( BTW and off topic, but early 629s seem to have soft yokes.)

 

[handejector]

I can see the burr standing on the left side of the barrel stub that is making those marks----

That burr needs to be stoned off.
As steelslaver and jaymore said, the yoke screw probably also has a problem. A 29-4 should have the new system with the V groove and a yoke screw with the plunger. Check the plunger for free operation.

 

[Giorgio Italy]

Hello friends
I take advantage of your patience ... and forgive my poor language ...
Here are the test benches of Liège (barrel, frame and cylinder) and the Italian one of Gardone val Trompia - Brescia (plus the italian catalog number)