Model 66 - binding after 100 rounds

Flint Ridge

Flint Ridge

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Picked up a used 66-1. Does not seem like it has been abused other than some finish issues. Was able to put 125 or so rounds through it last weekend and toward the end it would sometimes bind drawing the hammer back for some SA work. Quick look at the forcing cone showed no excessive buildup in that area with FMJ, did not expect any problems there.

It has about .002 of endshake and otherwise pretty tight. I noticed a faint rub mark on the top of the forcing cone. Presume that is possibly it. Further staring as an uneducated new to revolver type, I finally noticed the slightest "wobble" in the Extractor Rod with the cylinder out and quickly spinning it. When rotating with the cylinder closed, the gap gets narrower by maybe .001 on two of the cylinders at max rotation.

So, I am presuming that I need to replace the Extractor Rod. Must say when I first got it that part looked older and dirtier than the rest of the gun and I wonder if it was not swapped with another one for sale.

Any additional thoughts? Other parts or suggestions - other than it is complete junk and send it to me to dispose of properly;)
 
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Are you sure it isn't just carbon and/or unburned gunpowder collecting under the ejector star?

My Redhawk will start to bind up after an extended period of shooting cast bullets. In its case, the debris from lube, unburned powder, carbon, etc. causes the cylinder itself to bind up on the crane. Have you tried rotating the cylinder with it open to see if there is any drag on it then?
 
Area under the ejector was good, I was just shooting .38 spls.

No problems with the cylinder binding on the crane and it only happened occassionally while shooting, like once or maybe twice per reload, toward the end. But that was post cleaning. The cylinder will freely spin when open.

The cylinder gap is pretty tight to start with on this one, just thinking that slight tweak might cause the issue.
 
A wobbling extractor rod is called "rod runout" and is corrected (or used to be anyway) by lightly rapping on the bent side of the rod with a round lead bar known as a babbit.
 
Take a good look at the cylinder to see if it has any wobble to it when you turn it. It could be the crane has been sprung a bit, usually by some ignorant yahoo that flipped the cylinder in and out after watching an old Cagney movie.

If its been sprung a trip to S&W is likely called for to make it perfect.
 
gunblade said:
A wobbling extractor rod is called "rod runout" and is corrected (or used to be anyway) by lightly rapping on the bent side of the rod with a round lead bar known as a babbit.
Click to expand...

A new extractor rod is a few bucks, so replacing and saving the old one would not be a concern there.

But I contemplated doing just what your are saying.
 
Steve C said:
Take a good look at the cylinder to see if it has any wobble to it when you turn it. It could be the crane has been sprung a bit, usually by some ignorant yahoo that flipped the cylinder in and out after watching an old Cagney movie.

If its been sprung a trip to S&W is likely called for to make it perfect.
Click to expand...

Looked at the crane so no obvious alignment issues. Certainly pondered the "cowboy" treatment. When spinning the cylinder it really seems to be just the Extractor Rod visibly wobbling, while the non-fluted portion of the cylinder seems perfectly aligned. Mind you I can't definitely say "no movement" at the front of the cylinder which is fluted.

Any suggestions or tricks to checking the crane?
 
Check the forcing cone,

Flint Ridge said:
Picked up a used 66-1. Does not seem like it has been abused other than some finish issues. Was able to put 125 or so rounds through it last weekend and toward the end it would sometimes bind drawing the hammer back for some SA work. Quick look at the forcing cone showed no excessive buildup in that area with FMJ, did not expect any problems there.

It has about .002 of endshake and otherwise pretty tight. I noticed a faint rub mark on the top of the forcing cone. Presume that is possibly it. Further staring as an uneducated new to revolver type, I finally noticed the slightest "wobble" in the Extractor Rod with the cylinder out and quickly spinning it. When rotating with the cylinder closed, the gap gets narrower by maybe .001 on two of the cylinders at max rotation.

So, I am presuming that I need to replace the Extractor Rod. Must say when I first got it that part looked older and dirtier than the rest of the gun and I wonder if it was not swapped with another one for sale.

Any additional thoughts? Other parts or suggestions - other than it is complete junk and send it to me to dispose of properly;)
Click to expand...

since these were fitted with a file there are more problems there than you might expect. If the b/c gap is significantly smaller at the top of the forcing cone, you could be getting cylinder rub there. If the fitter didn't hold the file all the way up against the topstrap a burr could be left at the top of the forcing cone. I've corrected revolvers with this problem by placing a metal shim against the topstrap, and filing off the high spot.
 
ms said:
since these were fitted with a file there are more problems there than you might expect. If the b/c gap is significantly smaller at the top of the forcing cone, you could be getting cylinder rub there. If the fitter didn't hold the file all the way up against the topstrap a burr could be left at the top of the forcing cone. I've corrected revolvers with this problem by placing a metal shim against the topstrap, and filing off the high spot.
Click to expand...

Alright, I see what you are saying, but it is not equal all the way around as the cylinder rotates. It changes about .001 and the closeness is only on 1/3 of the rotation that is notable. I'm talking about .001 movement if I recall the feeler gages properly.

Could a tweaked Extractor Rod cause the cylinder to be ever so slightly out of alignment?
 
Maybe I have multi issues going on and confusing me.

Certainly the Extractor Rod is tweaked and I have ordered a new one.

Binding so early in the round count has me a bit mystified - now certainly it is crud related in some way, but this seems too soon and not excessively dirty. Did drag my thumb across the forcing cone and no real buildup there. When cleaning there was "crud" building up (don't know the terms here) on the frame in the cutout area below the firing pin where the hand or land comes up and engages the extractor.

Could the slight metal on metal wear at the top of the forcing cone be from cylinder rebound?
 
The center pin inside the rod may also be bent. Put it on a flat surface and roll it while looking from the side to see if the light gap under it changes as it rolls. If it does either order a new one or carefully bend it with light taps. There is a Midway video on Youtube showing how to do this. I am betting the wear spot on the forcing cone is due to bent pin and rod. I had a 29-2 with similar problems solved by replacing the rod and pin. Be aware that the threads on older rods are right hand twist. I am not sure when the change from RT to Left happened but some 29-2s have either. I am not sure if the 66-1 had left or right. New center pins can be longer than needed for a K-frame so you might need to grind it to correct length.
 
tbury said:
The center pin inside the rod may also be bent. Put it on a flat surface and roll it while looking from the side to see if the light gap under it changes as it rolls. If it does either order a new one or carefully bend it with light taps. There is a Midway video on Youtube showing how to do this. I am betting the wear spot on the forcing cone is due to bent pin and rod. I had a 29-2 with similar problems solved by replacing the rod and pin. Be aware that the threads on older rods are right hand twist. I am not sure when the change from RT to Left happened but some 29-2s have either. I am not sure if the 66-1 had left or right. New center pins can be longer than needed for a K-frame so you might need to grind it to correct length.
Click to expand...

Almost ordered the pin as well, but did not. However, Midway USA has it in stock and my brother is putting in an order there, so on my way to work I'll swing by and pick it up at Midway's warehouse and avoid shipping costs as I always do.

Thanks, will have to report back and appreciate the tip on LH vs RH. I'll gently try to loosen clockwise first.
 
When disassembling the ejector rod assembly, first put three EMPTY cases in the cylinder to support the ejector.
This will prevent bending the ejector pins or stressing the ejector shaft.

The Model 66-1 is Right-hand threaded.
Grip the end of the rod with a padded vise and unscrew the cylinder by turning it.
Careful, the rod can be easily bent.
Make sure you turn it the right way. STOP and think about it before you try to turn it.

Once you have it apart, use a brass toothbrush to THOROUGHLY scrub the underside of the ejector and it's recess in the cylinder.
Tiny particles of grit can get caught there and will embed into the metal when the gun is fired.
This is a major cause of binding, especially binding that seems to come and go, or is only on two chambers.

You look and clean the area, but the tiny bit of grit is so small you can't see it. That's why you use a brass brush to scrub the area.
You also inspect for tiny bits of brass brush bristle caught there.
One owner recently had binding and couldn't find anything. I checked with a magnifier visor and found a bit of brass bristle.
 
tbury said:
The center pin inside the rod may also be bent. Put it on a flat surface and roll it while looking from the side to see if the light gap under it changes as it rolls. If it does either order a new one or carefully bend it with light taps. There is a Midway video on Youtube showing how to do this. I am betting the wear spot on the forcing cone is due to bent pin and rod. I had a 29-2 with similar problems solved by replacing the rod and pin. Be aware that the threads on older rods are right hand twist. I am not sure when the change from RT to Left happened but some 29-2s have either. I am not sure if the 66-1 had left or right. New center pins can be longer than needed for a K-frame so you might need to grind it to correct length.
Click to expand...

Well I replaced the rod and pin (ok I had to take it back apart to grind and polish to the proper length), cleaned everything up and it looks like it is turning true now.

Both the Rod and the Pin were both tweaked, the pin a lot more though.

Thanks all and tbury on the pin. We will see how it does but I am pretty confident this will help.
 
During a firing cycle, the following occurs:

1. Ignition of the cartridge expands the case and pushes the head of the cartridge case rearward to stop against the recoil shield.
2. Chamber pressure simultaneously pushes the cylinder forward, to the limit of cylinder endshake. If the endshake exceeds the B-C gap the face of the cylinder will touch against the breech ("forcing cone") end of the barrel.
3. As chamber pressure eases, the cartridge case contracts and the revolver is cycled again to repeat the cycle.

Any ejecta mass from the firing (bullet slivers, unburned powder granules, bullet lubricant, etc) can be hammered between cylinder face and barrel breech and temporarily stick. That is why the B-C gap needs to be within acceptable limits (nominally 0.004"-0.012"). The sticking is what jams the gun.
 
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