66-1 cylinder fit…

[Model29-26.5]

I recently purchased a used 66-1 Cylinder In order to convert it to 9 mm.
There is only one of my K frame magnums that I have not tried it in yet, and right now it Almost fits to my 66-1 4 inch But there is a bit of a rub and it’s not quite right.
I tried it in the others And it seems to have the same but worse.
The 4 inch 66-1 Is almost there, but not quite.
Typically, where would the problem be with this?
I’m sure if any of The experienced gunsmith among you felt What was happening, you’d know what it was as it seems to be the same kind of tight squeeze rub that’s happening on all of them.
It’s obviously stainless, But I tried it in three of my 19s.

Any help would be much appreciated.
Of course, it won’t be a problem if I take it to my local gunsmith, who is very well respected around here, But I really like to try to at least learn what the problem is even if I can’t fix it myself.

Last time I got an extra cylinder for a gun, it was a model 53 and the extra 22 LR that you could order. I found this one online, and it fit Perfectly. Smooth and shoots great.
I was hoping that this would be the case in at least one of my K frame magnum with the 66 cylinder, But it was not to be. I knew that these were not drop in parts, But since the 53 went so smoothly, I figured I would surely be able to get lucky with one of my 66 or 19.
Thanks

 

[Protocall_Design]

Since it's tight in all of them, I would clean well under the extractor and it's seat on the cylinder. If that doesn't make it fit better, it's likely that the crane barrel would need to be trimmed slightly shorter. You can install it without the crane to see how it fits. That may point you in the right direction.

 

[Model29-26.5]

Since it's tight in all of them, I would clean well under the extractor and it's seat on the cylinder. If that doesn't make it fit better, it's likely that the crane barrel would need to be trimmed slightly shorter. You can install it without the crane to see how it fits. That may point you in the right direction.

Thst may be the ticket.
I’ve tried it with the crane from the original gum and the crane that came with the cylinder. The crane that came with the cylinder is always a little tighter, So I might try trimming that, But I will need the tool.

 

[Protocall_Design]

You can use a case trimmer cutter with a 32 caliber pilot (5/16"). You may want to add a file handle and a longer pilot. The case trimmer pilots are very short. A 1" long pilot is about right. This helps keep the cut on the end perpendicular to the sides of the crane barrel.

 

[Model29-26.5]

You can use a case trimmer cutter with a 32 caliber pilot (5/16"). You may want to add a file handle and a longer pilot. The case trimmer pilots are very short. A 1" long pilot is about right. This helps keep the cut on the end perpendicular to the sides of the crane barrel.

Thanks. Hopefully Brownell’s will have them in stock.