How S&W checks cylinder gap today......

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fortyshooter

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Straight from the Tech's mouth.....

He told me they shoot for a gap of .004-.010.

The checking procedure is they insert the .004 gage in from one side and cycle the cylinder around and whatever size gage get's pulled to the other side is the final gap spec. on that revolver.

He said it "should" be the same on both sides but if a .011 doesn't go all the way through it could be shipped out.

Told him my M69 was returned back with .010 and .005 and he said to keep and eye on it to see if the wide side gets any larger from use or just send it back for another try.
 
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They do "shoot" for .004-.010. That's what I've been told also.
My snub got sent back for a .005-.011 gap. It shot horrible off to one side. But that's a 3".
I just got it back and shot it recently. They closed the gap and it shoots nicely (for a 3"). Took em 2-3 weeks to fix. Customer service was excellent and gave me no hassles.
Not being negative but yet another thing to check when buying new.
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Building revolvers correctly requires a degree of skill and attention to detail. I guess it's much easier to assemble CNC machined and MIM parts that just slide back and forth.
 
Go ahead and send it back again. I probably would. They need to get it closer than that. They will usually make good on things like that. It just a pain and I know a disappointment. I have a 329 pd I sent back a couple of times but it is great now. I tell you though, do not expect perfection from any of the makers. I think we enthusiastist scrutinize way more than even the above average consumer and things like your uneven bc gap do not even get noticed by most. I bet it is common with most swing out cylinder type revolvers due to tolerance stack in the many moving parts. Less common in single actions I bet.i know you can often get a feeler gauge to start through a gap but it will not pass all the way through or you feel a tighter spot. That tells you they have to be uneven. Just because you squeeze a gauge through does not mean it is even as it can have high or low spots and we are only talking a few thousandths.you would have to have some super narrow gauges to tell that.I am not going to check mine as it would just be one more thing for me to worry about��.
 
I have a model 60 safe queen bought new whose cylinder face rubbed up against the forcing cone. Sent it back and it was fixed. How it ever passed QC is beyond me. S&W is capable of doing better work than that. Maybe that's why the older guns are so popular and expensive.
 
I have one of the best gunsmiths in the country here in town and anything that goes out of his shop is set at .004. Not .003 or .005. Everything that gets adjusted is .004 unless the owner specifies different. The closer the better, but any build up and it will cause drag quickly. He told me the average shooter wouldn't know the difference until it got around .006 or .007 and then accuracy would start to fall off where you would really notice
 
Eddietruett said:
I have one of the best gunsmiths in the country here in town and anything that goes out of his shop is set at .004. Not .003 or .005. Everything that gets adjusted is .004 unless the owner specifies different. The closer the better, but any build up and it will cause drag quickly. He told me the average shooter wouldn't know the difference until it got around .006 or .007 and then accuracy would start to fall off where you would really notice
Click to expand...

I do not believe accuracy falls off with a larger gap. Velocity might(negligible ) but I shot some with large gaps that were accurate . I set mine to 6 to 8 thousands when I have set my barrel back because when I tried 4 thousandths I would have debris build up. But to each his own. Much of this is academic. As I get older I worry less about the minutia but how they shoot. I shot one of my 686s this afternoon after work that has a larger bc gap. With a hornady 158 grain xtp and 13.5 grains of 2400 I put 5 shots in about an inch at 25 yards off my rest. I can live with a 10 thousandths bc gap in a gun that shoots like that.
 
I think too tight a cylinder throat has more effect on accuracy than the barrel gap.
I honed out the throats to .4305 and will do more target shooting and see how it does.
Not in a big hurry to ship it back.

I am curious about that barrel sleeve installation tool they use which engages the rifling. How does it not raise or burr up the edges of the rifling??
 
My wife just bought me a 686+ PC for my birthday and the cylinder gap on it the .003 feeler gage will go all the way through and the .0035 won't .. checked from both sides .. checked each cylinder and all were the same ..

The measurements lead me to believe the barrel is true .. Still haven't shot it so can't say how it shoots but the action feels very smooth and does feel like you could stage the trigger though I don't do that .. since all I own is autos .. till now !!

They can be fine tuned .. guess its all according to which smith is doing the pistol you get !!
 
Whitwabit said:
My wife just bought me a 686+ PC for my birthday and the cylinder gap on it the .003 feeler gage will go all the way through and the .0035 won't .. checked from both sides .. checked each cylinder and all were the same ..

The measurements lead me to believe the barrel is true .. Still haven't shot it so can't say how it shoots but the action feels very smooth and does feel like you could stage the trigger though I don't do that .. since all I own is autos .. till now !!

They can be fine tuned .. guess its all according to which smith is doing the pistol you get !!
Click to expand...

Wow that is a tight one! All my revolvers, of different brands, are in the .006-.008 range.
 
fortyshooter said:
Wow that is a tight one! All my revolvers, of different brands, are in the .006-.008 range.
Click to expand...

Was just talking to a friend that said his tightest was 5 and the others he has are like yours in the .006 to .008 range .. I am happy with the .003 .. :)

I was surprised that it was this tight .. I checked it twice because I thought I had made a mistake .. That's why I called a friend who I knew had a number of revolvers .. to ask him what some of his were ..

None of his are Performance Center though !!
 
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dogdoc said:
I do not believe accuracy falls off with a larger gap. Velocity might(negligible ) but I shot some with large gaps that were accurate . I set mine to 6 to 8 thousands when I have set my barrel back because when I tried 4 thousandths I would have debris build up. But to each his own. Much of this is academic. As I get older I worry less about the minutia but how they shoot. I shot one of my 686s this afternoon after work that has a larger bc gap. With a hornady 158 grain xtp and 13.5 grains of 2400 I put 5 shots in about an inch at 25 yards off my rest. I can live with a 10 thousandths bc gap in a gun that shoots like that.
Click to expand...
I certainly can't argue with results. Only going by what I was told and my "smith" built a lot of competition revolvers back in the day. Personally I would be more worried about the velocity loss on my hunting revolvers and while I know the larger gap can effect velocity, how much I have no clue. I have 2 model 686 that I hunt with one is a 8 3/8" and other is a 7". With certain loads and powder, the velocity is about the same and with other loads there is a bigger difference in velocity between the 2 barrel lengths. There are just so many variables that one could do testing till dooms day and still not have all the answers. That's what makes loading and shooting so much fun for me.
 
fortyshooter said:
I think too tight a cylinder throat has more effect on accuracy than the barrel gap.
I honed out the throats to .4305 and will do more target shooting and see how it does.
Not in a big hurry to ship it back.

I am curious about that barrel sleeve installation tool they use which engages the rifling. How does it not raise or burr up the edges of the rifling??
Click to expand...
I'm a firm believer that the correct size bullet make a huge difference in how accurate a revolver is. I have 2 almost identical model 686's that I hunt/shoot out to around 80 yards since that's the limit of my backyard range. My 8 3/8" will shoot cast bullets sized to .358 so accurate it scares me and my 7" will shoot the same bullets in groups at 80 yards almost twice as large. Use a jacketed bullet sized to .357 and the accuracy completely reverses! I'm convinced that it is the diameter more so than cast vs jacketed. One day I'll try some .357 cast in the 7" just to confirm, but right now I'm set at least for the upcoming season. Cast for Hogs and jacketed for deer and coyotes.
 
Maybe I need to send it to the Performance Center for a blueprint job!

I bought it for some field carry and plinking.

For serious .44 shooting my 7.5 Ruger SBH comes out!
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I would think that with a gap that is .004 on one side and .010 on the other, that you would eventually get erosion on the larger gap side and then it would continue to get worse. That's just my thinking.
 
Older revolvers are not immune to gap problems either. I had a 38/44 that was so tight that after a couple cylinders of shooting it bound up terribly. I have experienced the same thing a time or two with other older S&W. It may be worse these days but it is not a new thing.
 
Marshal Kane said:
I have a model 60 safe queen bought new whose cylinder face rubbed up against the forcing cone. Sent it back and it was fixed. How it ever passed QC is beyond me. S&W is capable of doing better work than that. Maybe that's why the older guns are so popular and expensive.
Click to expand...


I doubt that every production gun gets checked by QC. Most likely, they have a sampling plan that requires inspection of select guns based on production numbers and past rejections. Old process that is effective. Unlike a certain manufacturer that doesn't seem to inspect anything - relies on the end user to be their inspector.
 
MRB1 said:
Unlike a certain manufacturer that doesn't seem to inspect anything - relies on the end user to be their inspector.
Click to expand...

You mean Tesla Motors? Latest about them is rear bumpers falling off their $60000+ Model 3's.

All Smith revolvers are test fired at the factory, correct? At least mine have come out of the box with powder burns on every other charge hole.

The whole point of a QC program is to NOT have to inspect every part, assembly, or finished product.
 
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