Cylinder binds slightly on two chambers

[adweisbe]

This story is a bit long

I was at the range and had a case stuck in the chamber that wouldn't extract easily. After ten or so decent hits to to the ejector (I opted for more hits rather then hitting harder) it came loose. At some point after that the cylinder became difficult to turn on two chambers.

I went home and tried to put the yoke/crane alignment tool through the yoke and there was a lot of resistance. I got it in the gun and things lined up fine. I thought I would try and ream it (oops) but I couldn't get the reamer in and I foolishly turned the handle with the reamer partially inserted. I was able to clean up the damage with some 600 grit wet or dry and now things are as they were before, actually a little bit better in that the cylinder doesn't bind as much on either chamber. The alignment tool has scratches on it from being run through the yoke, and I suspect that is from what I did with the reamer.

At this point I can tell that the cylinder doesn't spin freely. The outside of the yoke/inside of the cylinder is quite a bit rougher then I am used to seeing and I suspect that might be causing some of the binding. The rings on the cylinder and yoke are quite deep and the whole assembly is anything but smooth. I am considering polishing it with some 600 grit to see if that unbinds it, but I wanted to check here to see if that is a good idea.

Is there a step on the yoke/inside of the cylinder or is it the same diameter for the whole length? I am trying to understand if there is something I might damage while polishing other then making things out of round.

Photos follow.

Thanks

 

[john traveler]

The inside of the cylinder bore is a uniform diameter. That step you is where the gas ring (a separate part) is pressed in.

The roughness you describe is likely from a burr that developed from handling the crane. Did you drop it? Or from debris or grit inside the cylinder bore from polishing. A little bit of 600-grit polishing won't hurt. Just avoid excessive polishing that will increase cylinder-to-crane slop. I would degrease all parts after polishing (solvent or alcohol rinse) and relubricate before assembly. Cycle the gun a few hundred times to re-seat the moving parts and you should be good to go.

 

[adweisbe]

The inside of the cylinder bore is a uniform diameter. That step you is where the gas ring (a separate part) is pressed in.

The roughness you describe is likely from a burr that developed from handling the crane. Did you drop it? Or from debris or grit inside the cylinder bore from polishing. A little bit of 600-grit polishing won't hurt. Just avoid excessive polishing that will increase cylinder-to-crane slop. I would degrease all parts after polishing (solvent or alcohol rinse) and relubricate before assembly. Cycle the gun a few hundred times to re-seat the moving parts and you should be good to go.

Thanks, I polished it a bit and now it doesn't bind on any particular chamber. I don't think the yoke was dropped. There is a dent in the photos on the gas ring. Where the gas ring was pressed in there is a big big step. The machining on this gun is a joke. Chatter all over the place. It shoots so low that with a 6:00 hold it is off paper on a B2 target (plenty of other k-frames to confirm it isn't me). The cylinder doesn't spin freely, but neither does it bind.

 

[Dragon88]

Did you try simply cleaning under the extractor star when it became difficult to turn? Or did you go straight to your home brew "gunsmithing"?