K or J barrel?

[toad94]

I have this barrel that I got some time ago with the thought of making my M10 into a snubbie. After I got some more knowledge on what is involved in that process, I decided against it. I was told that it was a K frame barrel, but after holding it up next to my 10, it appears that it would have a major cylinder/barrel gap. It is marked 38 special, so I got to thinking it might be for a J frame? Do the K and J barrels have different diameters and lengths? If anyone could help, it would be greatly appreciated. Thanks.

[murphydog]

Based on the photo, it appears to be a J frame barrel. The K dimensions are different, but I'm sure one of the gunsmith/armorers on the Forum can give the specifics.

[toad94]

Thanks Murphydog. I am coming to the conclusion that this is for a J frame. I got some dial calipers and measured it. The diameter at the face that seats against the frame is about .665 and tapers to .590 at the muzzle end. Overall length is 1.983. This is a smaller diameter than the 3" barrel on my M10.

[WR Moore]

The important dimensions are those of the threaded shank. S&W uses the same 36 tpi thread on all their revolver barrels, but the diameter and length of the shank are different for different frames/models. There should be some dimensions here somewhere where someone was trying to install an L frame barrel on a K frame.

Your picture does look like a J frame barrel, but looks aren't definitive.

[tomcatt51]

J frame is .500-36
K frame is .540-36
L frame is .562-36

[toad94]

Ok. Based on the dimensions given, it is a K frame barrel. Thank you so much.