Question about 686 barrel

[squid8286]

A friend and I were talking tonight about S&W stuff in general. He has a 7-shot 686 that he said has a slightly over-torqued barrel that is barely noticeable. He said it was about a degree off to the right looking from the muzzle back. Somebody told him to boil the part of the gun where the barrel meets the frame because it is torqued down with Rocksett, and nothing will get that loose but boiling water. He wants to just line it back up to top dead center, and is trying to avoid taking the barrel loose. Is that the case? Does anyone know how Smith attaches the barrels these days? I knew they were screwed in, but I didn't know if they used some sort of adhesive or not on the barrel threads. At any rate, I told him I would get on here and ask around. Thank you.

 

[CH4]

After 1982 and the deletion of the barrel pin, the barrels were crush
fit. No adhesive was used. Never heard of the boiling water method. lol Just need the proper fixture so you don’t bend the frame. I can imagine over clocking it the wrong way. Bring it to a real gunsmith or send it to S&W.

 

[stansdds]

S&W barrels are screwed in, crush fit, even those with the pin. S&W, as far as I know, did not use any sort of adhesive on the threads. They may have applied a very small amount of oil or anti-seize to the threads as that is pretty common when using threaded fasteners.
For a barrel that has been over-torqued, backing it off to get the barrel rib into proper alignment with the frame may work ok, but it may also end up with insufficient torque to prevent the barrel from unscrewing itself during firing. An over torqued barrel might require milling the barrel shoulder so as to turn the barrel into the frame one additional turn to obtain proper torque.

 

[Protocall_Design]

The factory doesn't use any adhesive. They screw the barrel on tight enough that it won't loosen from shooting. Due to manufacturing tolerances, I have seen a few exceptions to this rule. The tolerance thing is the same for every part on a gun. Not every part is perfect.

Normally, it's a simple matter, with a bench vise and frame wrench, to just tweak the position of the barrel a smidge. That job would take me about 10 minutes, half of that time would be getting tools out and set up.

 

[WR Moore]

I don't recall off the top of my head what the factory accepts as proper orientation of the front sight. That said, if the front sight is actually only 1 degree off dead vertical, best to leave well enough alone. It's real easy to be a bit short of vertical and make one last try and end up past vertical.

When I rebarreled revolvers, I did several tighten to near vertical, then loosen cycles to burnish the surfaces to make things easier. A little dab of moly chassis lube on frame & barrel shoulder helps too.

The "crush fit" really isn't that. You're actually stretching the threaded part/shaft of the barrel/bolt/stud. Why you're supposed to trash overtorqued bolts/studs in critical use.

Having said all that, if the barrel is a rifled tube with a separate shroud, the issue is really shroud to frame alignment stud fit. (Shroud stud to frame hole?)

 

[squid8286]

I appreciate the info. I don't know how much this concerns my buddy, but I will pass it along to him. Thanks, folks!