Ah, who needs range rods. Apparently Me.

[-BTM-]

So this range rod is as tight a fit as I could get for *all* my .357 barrels. I'm guessing runout is only a thou or two. The business end tapers to a point and it has a shoulder for catching the chamber or brass rim. Everything passes, until now.

I have a 586 that just kinda sits around waiting for a new sight insert. Thought I'd check it, and behold: the pointy end isn't seating in the firing pin hole. It should. All indications are that the barrel isn't square to the frame. (First pic)

I've been wondering since seeing the frame mating surface on Bob the 586. Visible milling marks, no sign of any effort to square it up. (Second pic)

They are both coming off, I'm going to try to make some kind of lapping tool to see what's up. Might cut the shank off a junk barrel and use it to protect the threads.

 

[Shotguncoach]

The next thing I'd be curious about on that frame would be the alignment of the threads in the frame. If you made a similar tool that would thread into the frame in place of the barrel it could help win narrow down where the out of alignment condition originates.

You might also check out the comments from @steelslaver in this thread.

 

[-BTM-]

The next thing I'd be curious about on that frame would be the alignment of the threads in the frame. If you made a similar tool that would thread into the frame in place of the barrel it could help win narrow down where the out of alignment condition originates.

You might also check out the comments from @steelslaver in this thread.

Thanks, that thread was interesting. I think I might be on to something though - The barrel was a b**** to remove, when it gave it made a big bang and went from tight to loose suddenly. Had to build a better barrel vise and use a 3' bar on the frame wrench.

Lo and behold, the contact pattern showed all top right and when threading the barrel back on it would lock up suddenly at about 10:30. If that put enough pressure on the barrel, it would move it in the direction the range rod shows.

What I'm trying to say is, the barrel was obviously too short. I fixed that.

Actually this makes me even more interested in making a lapping fixture for the frame face.