Gap between barrel lug and frame

[boing]

I bought a used 29-8 Mountain Gun yesterday. There's a gap between the frame and the lower part of the barrel lug, which gets narrower closer to the barrel and closes at the top of the cut out for the ejector rod. No gaps around the barrel area. The gap is about .008 at the widest part (the very bottom).

Is this a functional problem, or just a symptom of a late model Smith's QC?

 

[Jim Watson]

I've seen similar for years.
No mechanical problem, just cosmetic sloppiness.

 

[C.R.Sam]

Agree with Jim Watson.

No sweat, just sloppy.

Sam

 

[Standing Wolf]

It's conclusive evidence of sloppy manufacturing. If the gun's accurate, there's no need to worry about it. If 'twere mine, I'd turn it over to my friendly local gunsmith to have it trued up, just because I'm a little nutty that way, and I'd have him go over it with a fine-toothed comb, too: I'd have to be afraid if Smith & Wesson was that sloppy with the barrel, it might have been equally sloppy somewhere else.

 

[boing]

Thanks. I find myself becoming increasingly nuttier in that way, as well. But if it functions fine, I can live with it. I'll just always look at it from an angle.

I gave the gun what I thought was a pretty good going over: cylinder mechanics, bluing, crown, sideplate fit, etc... and except for the largish b/c gap (also 0.008 ), everything looks up to snuff to my inexperienced eye. Kind of miffed that I still missed what has now become an obvious error, but at least it's not major (yet). I always miss something.

I haven't shot it for accuracy yet, but 50 offhand rounds at 10 yards didn't show any problems. I'll bench it next time out.

It's my first Smith, and if the DA trigger continues to smooth out, I think I'm going to like it pretty well, lock and MIM aside.

 

[Old Fuff]

Boing:

I know that some pistolsmiths, and I believe the S&W factory slightly relieve the large underlug’s to insure that when the barrel is screwed into the frame it will bear solidly on the barrel’s shoulders and not on the lug itself. These days, when cost considerations dictate speedy assembly that relief cut may be …. Shall we say …. Generous. Be that as it may, I think the gap you’re seeing is intentional. The question of it being excessive is a matter of perspective and judgment.

 

[boing]

Generous it is. But if it's a deliberate facet of the manufacturing process, then I can accept that more easily than if it were just a machining/fitting error.

Failure of the trigger to reset I don't accept so easily. Twice today while dry firing, the trigger went forward partway, then got hung up. A gentle nudge and it pops forward. It looks like there's a tiny burr on the bottom corner of the sticky-outy part of the hammer face, and it may be catching on the little slidey-plate-thingy as the slidey-thingy is trying to come up between the hammer and the frame. Know what I mean?

I sure could use a schematic.

 

[C.R.Sam]

boing...
Scary, you paint a decent picture for me.

I think more likely there is some crud that got in behind the trigger and is messing up the free travel of the trigger return block and/or the trigger return spring.

If you know how to PROPERLY pull the sideplate, do so and give it a good cleaning. Just might fix it up.

Sam

 

[boing]

Sideplate removal as covered here?:

http://www.thehighroad.org/showthread.php?s=&threadid=26980

I'll see if I can pick up the appropriate screwdrivers when I go shopping for .44mag dies tomorrow.

 

[Old Fuff]

Boing:

Before you pop the sideplate (If you haven't already done so).

Remove the grips, and squirt a little "Gunscrubber" or a similar solvent/cleaner around the rebound slide (the part the trigger return spring fits into).

Follow this with a squirt of light gun oil and then double-action the gun a bit.

If this doen't work, then pop the sideplate.

 

[C.R.Sam]

Agree with Fuff the Elder.
The less plate poppin the better.


Sam

 

[boing]

Too late. There's a lot of scary stuff going on in there.

Everything looked pretty clean. I pulled the hammer and gently polished the underside where it rides over the angle on the rebound slide. The MIM surface was pretty rough, especially compared to the clean machining on the slide. I'll let dry firing do the rest. I managed not to bugger up the screws or sideplate this time, but my luck is as limited as my patience. I don't want to go back in there anytime soon.

 

[Old Fuff]

If this doesn't do the trick try the following:

Unlatch and swing out the cylinder.

Hold back the thumbpiece so that you can double-action the trigger.

If the trigger sticks reach into the cylinder window and push down on the cylinder stop. See if this releases the trigger and it goes forward like it should.

Sometimes the little spring in front of the cylinder stop gets kinked or bent out of place. Since the stop doesn't move like it should when the returning trigger comes to it the trigger stops.

Not likely to happen, but possible.