Yoke replacement --> tight cylinder?

[PeteC]

I am trying to replace a yoke on a K frame.

The new/used yoke fits the frame on its own, but not with the cylinder.

Without the cylinder, the yoke opens and closes as expected. However, when the cylinder is on the new yoke, it is very tight. Turns fine on its own, but not when closed.

Hard to close or open, and will not turn, or not easily. The ejector rod (left hand thread) will NOT unscrew.

The cyl. release latch moves normally. There is a visible cylinder gap, so the cylinder is not touching the forcing cone.

When closed the cylinder can be turned by hand a little, but it is obviously binding somewhere. ZERO end shake or side to side movement, so it is binding somewhere.

The gun is a Model 15-5, vintage about 1988, and was a police surplus gun several years ago. It was not very attractive cosmetically, sat on the shelf, and was loaned to me for a while by the original owner, now mine for a small-ish pittance.

While cleaning it, I noticed that for some reason it had been assembled with a yoke from a Model 19 or similar frame. I decided to replace it with the correct one, because... wellll, just because,

 

[armorer951]

As long as the cylinder assembly will fit into the space provided in the frame without the yoke.......I would guess that the barrel of the new yoke is too long to accommodate the cylinder assembly and close properly into the frame. If the cylinder will turn by hand on the new yoke after installation (closing), the excess material on the yoke would be small. (be sure to check under the extractor for dirt and debris and clean the entire cylinder assembly well before proceeding)

You can confirm this by de-greasing and staining the end of the yoke barrel with Sharpie or Dykem, and then re-assembling the cylinder assembly onto the yoke, and closing. After closing, turn the cylinder a turn or two and remove. Is the stain you applied to the yoke barrel gone? If so, the yoke barrel is likely too long, and will need to be shortened.

I can send you a facing reamer to use if you ultimately determine the yoke will need to be shortened. This tool will keep the end of the yoke at 90° during the process. Stoning is also an option if you have a hard India stone on hand.

If you're not comfortable with fitting the assembly yourself, I suggest taking the revolver to your nearest trained/trusted/vetted gunsmith.

Carter

 

[PeteC]

The cylinder DID fit fine with the old yoke. I even fired this gun, about two years ago. It was purchased with three (?) others from an online shop that sold trade-in police surplus guns, before Covid.

If by "cylinder assembly", you mean cylinder and extractor, then yes, it fits, and I can dry fire the gun without the yoke.

I can-NOT turn the cylinder, by hand or otherwise, assembled with the new/used yoke, when the cylinder is fully closed and latched. Maybe a little bit, less than 1/4 turn.

If I reassemble the gun with the parts it came with, including the yoke I am trying to replace, it works fine.

I can disassemble a revolver, clean it, measure end shake and use end shake shims/bearings, and I have access to some gunsmithing hand tools, but not a machine shop.

 

[armorer951]

If the new yoke is of the same design (comparing gas ring in the cylinder style vs gas ring on the yoke) as the one that was in the assembly previously and worked fine.... I believe your assessment confirms that the barrel of the new yoke is too long.

Have you measured the length of the yoke barrels to compare them?

Also, make sure the gas ring on the cylinder (if there is one) is not binding on the yoke at the front after closing.

Carter

 

[PeteC]

I have not measured the yoke barrels, or anything else except the cylinder gap, so far. No gas ring on either yoke.

 

[armorer951]

Is that your "new" yoke in the photo in post 3?

If it is, I believe it may be from a later model that uses the new yoke retention screw. This would be incompatible with your 15-5, according to the Catalog.

 

[PeteC]

Is that your "new" yoke in the photo in post 3?

If it is, I believe it may be from a later model that uses the new yoke retention screw. This would be incompatible with your 15-5, according to the Catalog.

No, that was the one which was on the gun, and it has the v-shaped groove.

The one I am trying to fit was on the gun, and I was in too much hurry to disassemble it to take the pic.

edit:

The shape of the yoke that was on the gun, it looks like it came from a Model 19 frame or similar.